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This paper examined the application of ion bombardment (IB) and NH3 plasma treatment (PT) techniques in fabricating a high-performance Si3N4 charge storage layer. The IB technique can be used for creating numerous additional trap sites in the storage layer to enhance charge trapping efficiency and also causes changes in trap centroid location. In addition, the effect of centroid location on operation efficiency and reliability was investigated. Using gate-sensing and channel-sensing analysis, the changes in centroid location were demonstrated. In addition, the energy-level distribution of trap sites was clearly delineated by performing discharge-based multipulse analysis. The NH3 PT technique can substantially passivate IB-induced shallow trap sites to increase data retention time. The influence of the NH3 PT time on the memory characteristics of an IB-induced Si3N4 sample was investigated. The optimal characteristics of an ion-bombarded and plasma-passivated Si3N4 storage layer are presented. Compared with the conventional Si3N4 storage layer, the optimal ion-bombarded and plasma-passivated Si3N4 sample exhibited higher operation efficiency and superior reliability. [ABSTRACT FROM PUBLISHER]

Ge is a candidate for replacing Si, especially for pMOSFETs, because of its high hole mobility. For Si-pMOSFETs, negative-bias temperature instabilities (NBTI) limit their lifetime. There is little information available for the NBTI of Ge-pMOSFETs with Ge/GeO2/Al2O3 stack. The objective of this paper is to provide this information and compare the NBTI of Ge- and Si-pMOSFETs. New findings include: 1) the time exponent varies with stress biases/field when measured by either the conventional slow dc or pulse I-V technique, making the conventional Vg -accelerated method for predicting the lifetime of Si-pMOSFETs inapplicable to Ge-pMOSFETs used in this paper; 2) the NBTI is dominated by positive charges (PCs) in dielectric, rather than generated interface states; 3) the PC in Ge/GeO2/Al2O3 can be fully annealed at 150 ^\circC ; and 4) the defect losses reported for Si sample were not observed. For the first time, we report that the PCs in oxides on Ge and Si behave differently, and to explain the difference, an energy-switching model is proposed for hole traps in Ge-MOSEFTs: their energy levels have a spread below the edge of valence band, i.e., Ev , when neutral, lift well above Ev after charging, and return below Ev following neutralization. [ABSTRACT FROM PUBLISHER]

This paper considers the Cauchy problem of solutions for a class of sixth order 1-D nonlinear wave equations at high initial energy level. By introducing a new stable set we derive the result that certain solutions with arbitrarily positive initial energy exist globally. [ABSTRACT FROM AUTHOR]

Eu-MOF was designed and synthesized,which can be used as a high sensitivity, multi-response fluorescence sensor for the efficient detection of aniline (ANI), nitrobenzene (NB), ornidazole (ORN), phryridine (FLU) and can also be used for fluorescence anti-counterfeiting and test paper detection. [Display omitted] • A Eu-MOF was synthesized, can efficiently and sensitively detect a variety of contaminants in water: ANI, NB, ORN and FLU. • Eu-MOF can quantitatively detect aniline (ANI) in aqueous solution by proportional fluorescence. • Eu-MOF has strong anti-counterfeiting ability and good stability, and can be used as anti-counterfeiting ink material. • Eu-MOF has good selectivity to FLU and can be used for rapid in situ imaging of pesticide residues. A new Europium metal–organic framework (Eu-MOF), namely [Eu(dpa) (H 2 O)]·0.5(bpy)·4H 2 O} n (H 4 dpa = 5-(3,4-dicarboxyphenoxy) isophenic acid, bpy = protonated 4,4′-bipyridine) was synthesized and structurally characterized by elemental analyses, infrared spectroscopy, and X-ray single-crystal diffraction analyses. Eu-MOF shows a three-dimensional network structure based on EuIII ions and (dpa)4− ligands via µ 4 : η1, η2, η2, η2 coordination mode. Fluorescence analysis shows that Eu-MOF has excellent fluorescence sensing characteristics, which can efficiently and sensitively detect various pollutants in water: the limit of detection (LOD) of ratiometric fluorescence detection of ANI in water was 42.9 nM, which was better than the single-peak detection limit. In addition, the peak detection limits of Eu-MOF for Flu, ORN and NB were 120 nM, 27 nM and 94 nM, respectively. In addition, XPS, LUMO orbital energy level, fluorescence lifetime, ultraviolet absorption and other principles are used to explore the mechanism of fluorescence quenching. Surprisingly, Eu-MOF not only has excellent anti- counterfeiting ability and stability, can be used as anti-counterfeiting material in life, but also has good selectivity to Flu. Eu-MOF has obvious fluorescence quenching effect on Flu on paper under ultraviolet light, which can be used for rapid in situ imaging test paper of pesticide residues. [ABSTRACT FROM AUTHOR]

Based on Marcus theory, the photoinduced charge transfer characteristics of D-A type organic solar cells (OSCs) under the influence of external electric field ( F ext) are studied in this paper. The properties of excited states under F ext are studied, and the change of three parameters related to charge transfer rate, namely reorganization energy (λ), Gibbs free energy (Δ G) and charge transfer integral (V da), with F ext is calculated. Finally, the variation of charge transfer rate with F ext is obtained. The results show that the charge transfer rate is regulated by F ext , and the change of V da under F ext is the main factor affecting the charge transfer rate. [Display omitted] • Based on Marcus theory, the photoinduced charge transfer characteristics of D-A all-small molecule OSCs under the influence of F ext are studied in this paper. • The F ext has little influence on λ and Δ G, it modulates the charge transfer rate mainly by influencing V da. • The electron transition energy of ICT states is more easily affected by F ext than that of LE states. • The F ext may modulate charge transfer modes. In this paper, MTDATA is selected as the electron donor and BPhen as the acceptor. The trianiline structure of the donor molecule provides a variety of charge transfer pathways for charge separation. Based on Marcus theory, the photoinduced charge transfer properties of non-fullerene acceptor organic solar cells (NFA-OSCs) in external electric field ( F ext) were studied. By analyzing the changes of reorganization energy (λ), Gibbs free energy (Δ G), electron transfer integral (V da) and charge transfer rate under the influence of F ext , it was found that F ext can effectively regulate the charge transfer. Moreover, the change of charge transfer rate under F ext is similar to V da , indicating that V da is the main factor affecting charge transfer rate. To a certain extent, this study provides theoretical support for improving the photoelectric performance of NFA-OSCs. [ABSTRACT FROM AUTHOR]

Purpose: Corneal crosslinking (CXL) procedures are the treatment of choice in halting progressive corneal ectasia and preserving visual acuity due to keratoconus. Pulsed crosslinking (P-CXL) was developed using intermittent pulsing ultraviolet (UV) light to mitigate the depletion of oxygen levels that occurs with continuous UV exposure in standard crosslinking protocols (C-CXL). This study aimed to explore the use of P-CXL in the treatment of keratoconus and determine whether the availability of oxygen in P-CXL carries superior efficacy outcomes as an alternative to C-CXL modalities.This review was undertaken in accordance with PRISMA guidelines. A search of several databases conducted with two separate reviewers resulted in 29 papers meeting inclusion criteria for the review, 14 selected for meta-analysis. Primary outcomes assessed by the included papers included maximum keratometry (Kmax), corrected and uncorrected distance visual acuity (CDVA, UDVA), and secondary outcomes included central corneal thickness (CCT), endothelial cell count and demarcation line. Statistical analyses were carried out on Review Manager 5.4 and the meta-analysis employed a random-effects model, which estimated the weighted effect size of raw means using inverse variance weights.At 12 months P-CXL showed statistically significant reductions in Kmax (-0.75 D; p < 0.001) and improvement in CDVA (-0.10 logMAR; p < 0.001) compared to baseline. The meta-analysis of comparative studies determined that mean differences in Kmax, CDVA, UDVA, Kmean and CCT after 12 months were not statistically significant between pulsed and continuous crosslinking groups.Overall, P-CXL is effective in improving visual acuity and keratometry outcomes in keratoconus. The meta-analysis did not show a statistically significant difference in Kmax and CDVA between P-CXL and C-CXL, indicating a non-inferiority of P-CXL. However, findings of the meta-analysis are limited by the fact that different energy levels and exposure times were used for P-CXL in comparison to C-CXL in some studies, making it unsuitable to determine whether the efficacy of CXL is improved by the use of pulsed light.What is Known• Pulsed crosslinking (P-CXL) uses intermittent UV light to prevent oxygen depletion when using higher energy protocols, unlike continuous UV exposure in standard continuous crosslinking (C-CXL).• This should theoretically enhance the efficacy of the treatment by maintaining higher oxygen levels that are crucial to the cross-linking process.• There are no systematic reviews or meta-analyses directly comparing the efficacy or safety of P-CXL to C-CXL.What is New• Meta-analysis revealed differences in keratometry between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (Kmax -0.04 dioptres; p = 0.84).• Meta-analysis revealed differences in visual acuity between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (CDVA -0.01 logMAR letters; p = 0.57).• The use of intermittent pulsing in higher energy CXL protocols renders statistically similar outcomes as continuous light exposure at equivalent fluence (7.2 J/cm2) Methods: Corneal crosslinking (CXL) procedures are the treatment of choice in halting progressive corneal ectasia and preserving visual acuity due to keratoconus. Pulsed crosslinking (P-CXL) was developed using intermittent pulsing ultraviolet (UV) light to mitigate the depletion of oxygen levels that occurs with continuous UV exposure in standard crosslinking protocols (C-CXL). This study aimed to explore the use of P-CXL in the treatment of keratoconus and determine whether the availability of oxygen in P-CXL carries superior efficacy outcomes as an alternative to C-CXL modalities.This review was undertaken in accordance with PRISMA guidelines. A search of several databases conducted with two separate reviewers resulted in 29 papers meeting inclusion criteria for the review, 14 selected for meta-analysis. Primary outcomes assessed by the included papers included maximum keratometry (Kmax), corrected and uncorrected distance visual acuity (CDVA, UDVA), and secondary outcomes included central corneal thickness (CCT), endothelial cell count and demarcation line. Statistical analyses were carried out on Review Manager 5.4 and the meta-analysis employed a random-effects model, which estimated the weighted effect size of raw means using inverse variance weights.At 12 months P-CXL showed statistically significant reductions in Kmax (-0.75 D; p < 0.001) and improvement in CDVA (-0.10 logMAR; p < 0.001) compared to baseline. The meta-analysis of comparative studies determined that mean differences in Kmax, CDVA, UDVA, Kmean and CCT after 12 months were not statistically significant between pulsed and continuous crosslinking groups.Overall, P-CXL is effective in improving visual acuity and keratometry outcomes in keratoconus. The meta-analysis did not show a statistically significant difference in Kmax and CDVA between P-CXL and C-CXL, indicating a non-inferiority of P-CXL. However, findings of the meta-analysis are limited by the fact that different energy levels and exposure times were used for P-CXL in comparison to C-CXL in some studies, making it unsuitable to determine whether the efficacy of CXL is improved by the use of pulsed light.What is Known• Pulsed crosslinking (P-CXL) uses intermittent UV light to prevent oxygen depletion when using higher energy protocols, unlike continuous UV exposure in standard continuous crosslinking (C-CXL).• This should theoretically enhance the efficacy of the treatment by maintaining higher oxygen levels that are crucial to the cross-linking process.• There are no systematic reviews or meta-analyses directly comparing the efficacy or safety of P-CXL to C-CXL.What is New• Meta-analysis revealed differences in keratometry between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (Kmax -0.04 dioptres; p = 0.84).• Meta-analysis revealed differences in visual acuity between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (CDVA -0.01 logMAR letters; p = 0.57).• The use of intermittent pulsing in higher energy CXL protocols renders statistically similar outcomes as continuous light exposure at equivalent fluence (7.2 J/cm2) Results: Corneal crosslinking (CXL) procedures are the treatment of choice in halting progressive corneal ectasia and preserving visual acuity due to keratoconus. Pulsed crosslinking (P-CXL) was developed using intermittent pulsing ultraviolet (UV) light to mitigate the depletion of oxygen levels that occurs with continuous UV exposure in standard crosslinking protocols (C-CXL). This study aimed to explore the use of P-CXL in the treatment of keratoconus and determine whether the availability of oxygen in P-CXL carries superior efficacy outcomes as an alternative to C-CXL modalities.This review was undertaken in accordance with PRISMA guidelines. A search of several databases conducted with two separate reviewers resulted in 29 papers meeting inclusion criteria for the review, 14 selected for meta-analysis. Primary outcomes assessed by the included papers included maximum keratometry (Kmax), corrected and uncorrected distance visual acuity (CDVA, UDVA), and secondary outcomes included central corneal thickness (CCT), endothelial cell count and demarcation line. Statistical analyses were carried out on Review Manager 5.4 and the meta-analysis employed a random-effects model, which estimated the weighted effect size of raw means using inverse variance weights.At 12 months P-CXL showed statistically significant reductions in Kmax (-0.75 D; p < 0.001) and improvement in CDVA (-0.10 logMAR; p < 0.001) compared to baseline. The meta-analysis of comparative studies determined that mean differences in Kmax, CDVA, UDVA, Kmean and CCT after 12 months were not statistically significant between pulsed and continuous crosslinking groups.Overall, P-CXL is effective in improving visual acuity and keratometry outcomes in keratoconus. The meta-analysis did not show a statistically significant difference in Kmax and CDVA between P-CXL and C-CXL, indicating a non-inferiority of P-CXL. However, findings of the meta-analysis are limited by the fact that different energy levels and exposure times were used for P-CXL in comparison to C-CXL in some studies, making it unsuitable to determine whether the efficacy of CXL is improved by the use of pulsed light.What is Known• Pulsed crosslinking (P-CXL) uses intermittent UV light to prevent oxygen depletion when using higher energy protocols, unlike continuous UV exposure in standard continuous crosslinking (C-CXL).• This should theoretically enhance the efficacy of the treatment by maintaining higher oxygen levels that are crucial to the cross-linking process.• There are no systematic reviews or meta-analyses directly comparing the efficacy or safety of P-CXL to C-CXL.What is New• Meta-analysis revealed differences in keratometry between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (Kmax -0.04 dioptres; p = 0.84).• Meta-analysis revealed differences in visual acuity between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (CDVA -0.01 logMAR letters; p = 0.57).• The use of intermittent pulsing in higher energy CXL protocols renders statistically similar outcomes as continuous light exposure at equivalent fluence (7.2 J/cm2) Conclusions: Corneal crosslinking (CXL) procedures are the treatment of choice in halting progressive corneal ectasia and preserving visual acuity due to keratoconus. Pulsed crosslinking (P-CXL) was developed using intermittent pulsing ultraviolet (UV) light to mitigate the depletion of oxygen levels that occurs with continuous UV exposure in standard crosslinking protocols (C-CXL). This study aimed to explore the use of P-CXL in the treatment of keratoconus and determine whether the availability of oxygen in P-CXL carries superior efficacy outcomes as an alternative to C-CXL modalities.This review was undertaken in accordance with PRISMA guidelines. A search of several databases conducted with two separate reviewers resulted in 29 papers meeting inclusion criteria for the review, 14 selected for meta-analysis. Primary outcomes assessed by the included papers included maximum keratometry (Kmax), corrected and uncorrected distance visual acuity (CDVA, UDVA), and secondary outcomes included central corneal thickness (CCT), endothelial cell count and demarcation line. Statistical analyses were carried out on Review Manager 5.4 and the meta-analysis employed a random-effects model, which estimated the weighted effect size of raw means using inverse variance weights.At 12 months P-CXL showed statistically significant reductions in Kmax (-0.75 D; p < 0.001) and improvement in CDVA (-0.10 logMAR; p < 0.001) compared to baseline. The meta-analysis of comparative studies determined that mean differences in Kmax, CDVA, UDVA, Kmean and CCT after 12 months were not statistically significant between pulsed and continuous crosslinking groups.Overall, P-CXL is effective in improving visual acuity and keratometry outcomes in keratoconus. The meta-analysis did not show a statistically significant difference in Kmax and CDVA between P-CXL and C-CXL, indicating a non-inferiority of P-CXL. However, findings of the meta-analysis are limited by the fact that different energy levels and exposure times were used for P-CXL in comparison to C-CXL in some studies, making it unsuitable to determine whether the efficacy of CXL is improved by the use of pulsed light.What is Known• Pulsed crosslinking (P-CXL) uses intermittent UV light to prevent oxygen depletion when using higher energy protocols, unlike continuous UV exposure in standard continuous crosslinking (C-CXL).• This should theoretically enhance the efficacy of the treatment by maintaining higher oxygen levels that are crucial to the cross-linking process.• There are no systematic reviews or meta-analyses directly comparing the efficacy or safety of P-CXL to C-CXL.What is New• Meta-analysis revealed differences in keratometry between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (Kmax -0.04 dioptres; p = 0.84).• Meta-analysis revealed differences in visual acuity between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (CDVA -0.01 logMAR letters; p = 0.57).• The use of intermittent pulsing in higher energy CXL protocols renders statistically similar outcomes as continuous light exposure at equivalent fluence (7.2 J/cm2) Key messages: Corneal crosslinking (CXL) procedures are the treatment of choice in halting progressive corneal ectasia and preserving visual acuity due to keratoconus. Pulsed crosslinking (P-CXL) was developed using intermittent pulsing ultraviolet (UV) light to mitigate the depletion of oxygen levels that occurs with continuous UV exposure in standard crosslinking protocols (C-CXL). This study aimed to explore the use of P-CXL in the treatment of keratoconus and determine whether the availability of oxygen in P-CXL carries superior efficacy outcomes as an alternative to C-CXL modalities.This review was undertaken in accordance with PRISMA guidelines. A search of several databases conducted with two separate reviewers resulted in 29 papers meeting inclusion criteria for the review, 14 selected for meta-analysis. Primary outcomes assessed by the included papers included maximum keratometry (Kmax), corrected and uncorrected distance visual acuity (CDVA, UDVA), and secondary outcomes included central corneal thickness (CCT), endothelial cell count and demarcation line. Statistical analyses were carried out on Review Manager 5.4 and the meta-analysis employed a random-effects model, which estimated the weighted effect size of raw means using inverse variance weights.At 12 months P-CXL showed statistically significant reductions in Kmax (-0.75 D; p < 0.001) and improvement in CDVA (-0.10 logMAR; p < 0.001) compared to baseline. The meta-analysis of comparative studies determined that mean differences in Kmax, CDVA, UDVA, Kmean and CCT after 12 months were not statistically significant between pulsed and continuous crosslinking groups.Overall, P-CXL is effective in improving visual acuity and keratometry outcomes in keratoconus. The meta-analysis did not show a statistically significant difference in Kmax and CDVA between P-CXL and C-CXL, indicating a non-inferiority of P-CXL. However, findings of the meta-analysis are limited by the fact that different energy levels and exposure times were used for P-CXL in comparison to C-CXL in some studies, making it unsuitable to determine whether the efficacy of CXL is improved by the use of pulsed light.What is Known• Pulsed crosslinking (P-CXL) uses intermittent UV light to prevent oxygen depletion when using higher energy protocols, unlike continuous UV exposure in standard continuous crosslinking (C-CXL).• This should theoretically enhance the efficacy of the treatment by maintaining higher oxygen levels that are crucial to the cross-linking process.• There are no systematic reviews or meta-analyses directly comparing the efficacy or safety of P-CXL to C-CXL.What is New• Meta-analysis revealed differences in keratometry between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (Kmax -0.04 dioptres; p = 0.84).• Meta-analysis revealed differences in visual acuity between P-CXL and C-CXL groups with equivalent fluence (7.2 J/cm2) at 12 months were not statistically significant (CDVA -0.01 logMAR letters; p = 0.57).• The use of intermittent pulsing in higher energy CXL protocols renders statistically similar outcomes as continuous light exposure at equivalent fluence (7.2 J/cm2)  [ABSTRACT FROM AUTHOR]

The defossilization of industry has far-reaching implications regarding the future demand for hydrogen and other forms of energy. This paper presents and applies a fundamental bottom-up model that relies on techno-economic data of industrial production processes. Its aim is to identify, across a range of scenarios, the most cost-effective low-carbon options considering a variety of production systems. Subsequently, it derives the hydrogen and electricity demand that would result from the implementation of these least-cost low-carbon options in process industries in Germany. Aligning with the German government's target year for achieving climate neutrality, this study's reference year is 2045. The primary contribution lies in analyzing which hydrogen-based and direct electrification solutions would be cost-effective for a range of energy price levels under climate-neutral industrial production and what the resulting hydrogen and electricity demand would be. To this end, the methodology of this paper comprises the following steps: selection of the relevant industries (I), definition of conventional reference production systems and their low-carbon options (II), investigation and processing of the techno-economic data of the standardized production systems (III), establishment of a scenario framework (IV), determination of the least-cost low-carbon solution of a conventional reference production system under the scenario assumptions made (V), and estimation of the resulting hydrogen and electricity demand (VI). According to the results, the expected industrial hydrogen consumption in 2045 ranges from 265 TWh for higher hydrogen prices in or above the range of onshore wind-based green hydrogen supply costs, to up to 473 TWh for very low hydrogen prices corresponding to typical blue hydrogen production costs. Meanwhile, the direct electricity consumption of the process industries in the results ranges from 147 TWh for these rather low hydrogen prices to 338 TWh for the higher hydrogen prices in the region of or above the hydrogen supply costs from the electrolysis of energy from an onshore wind farm. Most of the break-even hydrogen prices that are relevant to the choice of low-carbon options are in the range of the benchmark purchase costs for blue hydrogen and green hydrogen produced from offshore wind power, which span between €40 per MWh and €97 per MWh. [Display omitted] • Derivation of the future hydrogen and power demand of the process industry in Germany. • Bottom-up, process-level model to find the least-cost low-carbon production method. • Reference year is 2045, and the achievement of climate-neutral production is assumed. • Model determines the hydrogen and power demand under varying hydrogen prices. • Expected hydrogen use between 265 TWh and 473 TWh, depending on scenario assumptions. [ABSTRACT FROM AUTHOR]

The simulation of lattice model systems for quantum materials is one of the most important approaches to understand quantum properties of matter in condensed matter physics. The main task in the simulation is to diagonalize a Hamiltonian matrix for the system and evaluate the electronic density of energy states. Kernel polynomial method (KPM) is one of the promising simulation methods. Because KPM contains a fine-grain recursive part in the algorithm, it is hard to parallelize it under the thread level parallelism such as on a supercomputer or a cluster computer. This paper focuses on methods to parallelize KPM on a massively parallel environment of GPU, aiming to achieve high parallelism for more speedups than the recent CPUs. This paper proposes two implementation methods called the full map and the sliding window methods, and evaluates the performances in the recent GPU platform. To enlarge available simulation sizes and at the same time to enhance the performance, this paper also describes additional optimization techniques depending on the GPU architecture. [ABSTRACT FROM AUTHOR]

Endurance is one of the key criteria for Flash memory technologies, particularly for the generations beyond 30 nm with high-\kappa materials. It is observed in this paper that the electron trapping in high-\kappa layers causes threshold-voltage window closure under dynamic program/erase cycling operations. This closure does not originate from the generation of new traps or from further trapping of electrons injected from the gate during erasing. By utilizing a recently developed multipulse technique, it is found that the energy distribution of the electron trapping in the high-\kappa layer significantly changes after cycling. Electron trapping at the deeper energy levels continuously increases as cycling proceeds, because it does not reach saturation within one programming pulse. The trapping in deep levels cannot be discharged under typical erase conditions, and an increase in deep-level trapping also causes a reduction of trapping at shallow levels. It is concluded that the window closure observed in this paper is caused by a combination of increased deep trapping after erasing and a reduction of shallow trapping after programming. [ABSTRACT FROM PUBLISHER]

In this paper, we examine the behavior of the quantum energy levels of a coupled oscillator system as the zero-order frequencies are varied to carry the corresponding classical system through a resonance. We find that the levels exhibit a pattern that is characteristic of the resonance. This pattern consists of clusters of levels, each containing a number of curves that run roughly parallel to one another and a number of curves that undergo pairwise narrowly avoided crossings. Adiabatic switching calculations show that the ‘‘parallel’’ curves are associated with states within the classical resonance region, while the narrowly avoiding curves are associated with states that are outside this region. It is further shown that the curves describing resonance states are formed from zero-order nonresonant curves by the overlap of many avoided crossings. This reorganization of multiply intersecting lines into parallel curves reflects the classical reorganization of phase space at a resonance. [ABSTRACT FROM AUTHOR]

We discuss the achievability of optimal control of the evolution of an unbounded quantum system by the action of external fields. Previous work has established that the evolution of a quantum system with a nondegenerate discrete and bounded spectrum of states can, in principle, be fully controlled, i.e., that the system wave function can be guided by external fields to approach arbitrarily closely a selected target state wave function. The optimal control of the evolution of a quantum system with a discrete and bounded spectrum of states has also been studied, using a method of analysis that depends on the localized character of bound state wave functions and the fact that the spectrum of states is bounded. In this paper, we examine whether it is possible to control, partially or fully, the evolution of an unbounded quantum system. We show that optimal control of the evolution of an unbounded quantum system is possible, in the sense that it is possible to minimize the difference between the product function formed at time t0 from a localizing function and a continuum wave function and a similarly defined target function at time tf.We have not been able to establish that such optimal control is equivalent to full control, i.e., that the difference between the initial and target functions can be made arbitrarily small, which would require showing that the set of control functions is complete with respect to the function space of the system. Our analysis establishes the existence of external fields that can optimally guide the unbounded system evolution in the absence of other constraints than the Schrödinger equation of motion, but does not provide an algorithm for the construction of such fields. The relationship between optimal control of the evolution of a quantum system and the existence of chaotic dynamics in the continuum domain is briefly discussed. We argue that the optimally controlled system cannot have chaotic dynamics even if the bare system... [ABSTRACT FROM AUTHOR]

This paper discusses the arc flash ramifications associated with the design and selection of medium-voltage switchgear. Three case studies are presented to demonstrate the impact of performing arc flash hazard analysis on the proposed and/or existing medium-voltage installation at the design stage. This paper proposes the following: 1) changes in the National Electrical Code, Article 110.16, to provide mandatory requirements for a) performing arc flash analysis at the design stage and b) placement of warning labels on switchgear to warn qualified persons of potential arc flash hazards and 2) a need to promulgate regulations requiring a utility company to notify its customers of changes in a) the available fault duty at the point of common coupling with a customer's facility and b) utility upstream protective device settings. [ABSTRACT FROM AUTHOR]

This paper proposes a method to determine the wavelength of unresolved transition arrays (UTAs) in the extreme ultraviolet (EUV) wavelength region from Sn to Hf plasma by combining calculated and experimental data. Based on a computational analysis of the atomic structure, we show that the wavelength of UTAs can be explained using the screening theory by a simple quadratic formula using the effective core charge and the screening constant for 4d electrons as parameters. The results from the model were compared with experiments to reproduce the trend of the spectrum, which has a minimum wavelength with respect to the ion charge. The wavelength is shown to agree with experiment over Pd- to Sr-like ions by applying a small shift that was determined using the spectrum observed in the electron beam ion trap. The present model would allow us to calculate the opacity of Sn plasmas with much smaller computational time than using present large-scale collisional radiative models, with fewer energy levels and parameterized rate coefficients, which will be also useful to investigate the efficiency of the EUV light source. [ABSTRACT FROM AUTHOR]

Copyright of Informacion Comercial Espanola Revista de Economia is the property of S.G.E.E.I.P.C., Secretaria de Estado de Comercio, Ministerio de Industria, Comercio y Turismo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We compute bound-state energies in two three-dimensional coupled waveguides, each obtained from the two-dimensional configuration considered in paper I [J. Math. Phys. 45, 1359–1379 (2004)] by rotating the geometry about a different axis. The first geometry consists of two concentric circular cylindrical waveguides coupled by a finite length gap along the axis of the inner cylinder, and the second is a pair of planar layers coupled laterally by a circular hole. We have also extended the theory for this latter case to include the possibility of multiple circular windows. Both problems are formulated using a mode-matching technique, and in the cylindrical guide case the same residue calculus theory as used in paper I is employed to find the bound-state energies. For the coupled planar layers we proceed differently, computing the zeros of a matrix derived from the matching analysis directly. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of rotation in the spin-1/2 non-relativistic Aharonov- Bohm problem for bound states. We use a technique based on the self-adjoint extension method and determine an expression for the energies of the bound states. The inclusion of the spin element in the Hamiltonian guarantees the existence of bound state solutions. We perform a numerical analysis of the energies and verify that both rotation and the spin degree of freedom affect the energies of the particle. The main effect we observe in this analysis is a cutoff value manifested in the Aharonov-Bohm flux parameter that delimits the values for the positive and negative energies. [ABSTRACT FROM AUTHOR]

The presence of copper contamination is known to cause strong light-induced degradation (Cu-LID) in silicon. In this paper, we parametrize the recombination activity of light-activated copper defects in terms of Shockley-Read-Hall recombination statistics through injection- and temperature dependent lifetime spectroscopy (TDLS) performed on deliberately contaminated float zone silicon wafers. We obtain an accurate fit of the experimental data via two non-interacting energy levels, i.e., a deep recombination center featuring an energy level at Ec - Et = 0:48 - 0:62 eV with a moderate donor-like capture asymmetry (k = 1:7 - 2:6Þ and an additional shallow energy state located at Ec - Et = 0:1 - 0:2 eV, which mostly affects the carrier lifetime only at high-injection conditions. Besides confirming these defect parameters, TDLS measurements also indicate a power-law temperature dependence of the capture cross sections associated with the deep energy state. Eventually, we compare these results with the available literature data, and we find that the formation of copper precipitates is the probable root cause behind Cu-LID. [ABSTRACT FROM AUTHOR]

In this paper we show that it is possible to use an iterative eigensolver in conjunction with Halverson and Poirier's symmetrized Gaussian (SG) basis [T. Halverson and B. Poirier, J. Chem. Phys. 137, 224101 (2012)] to compute accurate vibrational energy levels of molecules with as many as five atoms. This is done, without storing and manipulating large matrices, by solving a regular eigenvalue problem that makes it possible to exploit direct-product structure. These ideas are combined with a new procedure for selecting which basis functions to use. The SG basis we work with is orders of magnitude smaller than the basis made by using a classical energy criterion. We find significant convergence errors in previous calculations with SG bases. For sum-of-product Hamiltonians, SG bases large enough to compute accurate levels are orders of magnitude larger than even simple pruned bases composed of products of harmonic oscillator functions. [ABSTRACT FROM AUTHOR]

This is the second of two closely related articles (Paper I and Paper II) that together illustrate how research in physics education has helped guide the design of instruction that has proved effective in improving student understanding of atomic spectroscopy. Most of the more than 1000 students who participated in this four-year investigation were science majors enrolled in the introductory calculus- based physics course at the University of Washington (UW) in Seattle, WA, USA. The others included graduate and undergraduate teaching assistants at UW and physics majors in introductory and advanced physics courses at the University of Zagreb, Zagreb, Croatia. About half of the latter group were preservice high school physics teachers. Paper I describes how several conceptual and reasoning difficulties were identified among university students as they tried to relate a discrete line spectrum to the energy levels of atoms in a light source. This second article (Paper II) illustrates how findings from this research informed the development of a tutorial that led to improvement in student understanding of atomic emission spectra. [ABSTRACT FROM AUTHOR]

Expansion from coherent 2D spectroscopy to coherent 3D spectroscopy can provide significant advantages when studying molecules that have heavily perturbed energy levels. This paper illustrates such advantages by demonstrating how high resolution coherent 3D (HRC3D) spectroscopy can be used to study a portion of the visible spectrum of nitrogen dioxide. High resolution coherent 2D spectra usually contain rotational and vibrational patterns that are easy to analyze, but severe congestion and complexity preclude its effective use for many parts of the NO2 spectrum. HRC3D spectroscopy appears to be much more effective; multidimensional rotational and vibrational patterns produced by this new technique are easy to identify even in the presence of strong perturbations. A method for assigning peaks, which is based upon analyzing the resulting multidimensional patterns, has been developed. The higher level of multidimensionality is useful for reducing uncertainty in peak assignments, improving spectral resolution, providing simultaneous information on multiple levels and states, and predicting, verifying, and categorizing peaks. [ABSTRACT FROM AUTHOR]

In this paper, the degradation characteristics of MOS (Metal-Oxide-Semiconductor) stacks with Al2O3/AlON or Al2O3 only as dielectric layers on InGaAs were studied. The dielectric nitrides are proposed as possible passivation layers to prevent InGaAs oxidation. At negative bias, it has been found out that the main contribution to the overall degradation of the gate oxide is dominated by the generation of positive charge in the gate oxide. This effect is pronounced in MOS stacks with Al2O3/AlON as dielectric, where we think the positive charge is mainly generated in the AlON interlayer. At positive bias, the degradation is dominated by buildup of negative charge due to electron trapping in pre-existing or stress-induced traps. For stress biases where the leakage currents are low, the changes in the electrical characteristics are dominated by electron-trapping into traps located in energy levels in the upper part of the semiconductor gap. For stress biases with higher leakage current levels, the electron trapping occurs in stress-induced traps increasing the shift of VFB towards positive bias. The overall results clearly show that the improvement of the high-k dielectric/InGaAs interface by introducing N into the Al-oxide does not necessarily mean an increase in the reliability of the MOS stack. [ABSTRACT FROM AUTHOR]

This paper will address dosimetry and monitoring techniques for total ionizing dose (TID) testing of electronics devices. We will first discuss the basic principles of dosimetry, as well as the most common dosimetric quantities and units, used for the determination of the energy deposited in a given medium by ionizing radiation. In , we will give an overview of the available dosimetry techniques for ionizing radiation, along with the basic mechanisms exploited for their operation. In , we will address issues and factors affecting the dosimetry measurements, as well as we will give some practical “hints” about the selection and use of the presented techniques. Finally, a synthesis of the existing radiation test facilities, focusing on the one for TID testing, will be given in. Their interest, limitations, and some practical aspects involving the organization of radiation test campaigns will also be discussed in this paper. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the Yangian relations of Heisenberg spin chain systems. Firstly, we consider the closed XXZ spin chain model, through the Heisenberg spin XXZ model, we found the Hamiltonians for one kind system of three adjacent partial particles interaction systems. The model's constitution rules of energy levels and energy states which expand from the few-particle system to multi-particle system have good regularity. In this system, we found Yangian's law and illustrate it through graphs. Secondly, we further consider the closed XXZ spin chain's generalization of other three neighboring particles interaction systems from few-particle system to multi-particle system. Finally, we also discussed the laws of the three adjacent particles system of some models, they are the XXZ model with twist boundary condition, the open XXZ spin chain model and the XXZ model containing the next neighbor. In addition, not only XXZ model, XXX model, XY model and Ising model, but the relevant laws of spin-1 systems of these models were also discussed, they have similar rules to the XXZ model. Through calculation and research, the eigensystems of these models all have good Yangian and constitution laws. [ABSTRACT FROM AUTHOR]

The degree of linear polarization of the line x corresponding to the transition 1 s 2 p 3 P 2 → 1 s 2 1 S 0 is considered for Helium-like ions with non-zero nuclear spin. We are interested in this paper to seven ions: P 13 + , V 21 + , Mn 23 + , As 31 + , Rb 35 + , Y 35 + and Nb 39 + which are excited by electrons beam. In such ions, two kind of transitions occurs in the line x: the hyperfine-induced electric dipole E1 transition and the magnetic quadrupole M2 transition. From our results, we find that when we take into account this two kind of transitions without interference between the two channels E1 and M2, this leads to a drastic depolarization. However, the consideration of the interference effect leads to an increase in the polarization degree, slight for the whole line x and substantial for its individual hyperfine components. [ABSTRACT FROM AUTHOR]

This document is a technical paper titled "Efficient Perovskite quantum dots Light Emitting Diodes." It discusses the use of CsPbI3 perovskite quantum dots (QDs) in light-emitting diodes (LEDs) and the challenges faced in their practical applications. The paper presents a new strategy of proton-prompted short-chain ligand exchange in the synthesis of CsPbI3 QDs and the design of interface layers with high electron affinity. These approaches result in improved device performance, with a champion-level external quantum efficiency (EQE) of 25.80% achieved. This study represents the highest reported performance for pure red perovskite quantum dot LEDs to date. [Extracted from the article]

Opacity calculations performed within the expansion and the line-binned formalisms are reported for Sm V–X ions in this paper. These were determined by means of new large-scale atomic structure and radiative rate computations carried out using the pseudo-relativistic Hartree-Fock (HFR) method from which energy levels, wavelengths, and oscillator strengths were deduced for more than 100 millions of spectral lines in the considered samarium ions. In the absence of any experimental data, the reliability of HFR results was roughly estimated by comparison with those obtained with an independent theoretical approach, namely the fully relativistic multiconfiguration Dirac-Hartree-Fock method, in Sm VI and Sm VII. The opacities were estimated for typical conditions corresponding to early phases of kilonovae following neutron star mergers, i.e. for a density ρ  = 10−10 g cm−3, a time after the merger t  = 0.1 day and temperatures ranging from 25 000 to 70 000 K. In addition, the atomic calculations allowed us to establish the ground level for each of the Sm ions considered (still unknown until now), as well as reliable partition functions that are crucial for the determination of the ionization balance by solving the Saha equation and for accurate opacity calculations. [ABSTRACT FROM AUTHOR]

We have updated the isotopically invariant Dunham fit of O2 with newly reported literature transitions to derive (1) the energy levels, partition sums, band-by-band molecular constants, and RKR poten-tials for the X³Σg-, a¹Δg+, and b¹Σg+ states of the six O2 isotopologues: 16O16O, 16O17O, 16O18O, 17O17O, 17O18O, and 18O18O; (2) Franck-Condon factors for their a¹Δg- X³Σg-, b¹Σg+ - X³Σg-, and a¹Δg -- b¹Σg+ band systems. This new spectroscopic parameterization characterizes all known transitions within and between the X³Σg--, a¹Δg, and b¹Σg+ states within experimental uncertainty and can be used for accurate predictions of as yet unmeasured transitions. All of these results are necessary to provide a consistent linelist of all transitions which will be reported in a followup paper. [ABSTRACT FROM AUTHOR]

In previous works on Zn2 and Cd2 dimers we found that the long-range corrected CAMB3LYP gives better results than other density functional approximations for the excited states, especially in the asymptotic region. In this paper, we use it to present a time-dependent density functional (TDDFT) study for the ground-state as well as the excited states corresponding to the (6s² + 6s6p), (6s² + 6s7s), and (6s² + 6s7p) atomic asymptotes for the mercury dimer Hg2. We analyze its spectrum obtained from all-electron calculations performed with the relativistic Dirac-Coulomb and relativistic spinfree Hamiltonian as implemented in DIRAC-PACKAGE. A comparison with the literature is given as far as available. Our result is excellent for the most of the lower excited states and very encouraging for the higher excited states, it shows generally good agreements with experimental results and outperforms other theoretical results. This enables us to give a detailed analysis of the spectrum of the Hg2 including a comparative analysis with the lighter dimers of the group 12, Cd2, and Zn2, especially for the relativistic effects, the spin-orbit interaction, and the performance of CAMB3LYP and is enlightened for similar systems. The result shows, as expected, that spinfree Hamiltonian is less efficient than Dirac-Coulomb Hamiltonian for systems containing heavy elements such as Hg2. [ABSTRACT FROM AUTHOR]

The self-sensing tribological composite coating (Cu-14Al-X/SrAlO:Eu, Dy) for wear indicator is quenched because of vacuum pressure-assisted sintering method, which do harm to the monitoring of coating. In this paper, we constructed a model to explain the quenching mechanism of SrAlO:Eu, Dy in alloy coatings. The initial electron concentration and the energy level structures were studied. The results show that contact quenching rather than the traditional thermal quenching is the most important influencing factor for SrAlO:Eu, Dy. The contact metal in coatings can be as a defect level and dissipation center of electron transition, the quenching process could be well explained by the model we proposed. [ABSTRACT FROM AUTHOR]

For a magnetic geodesic flow on the 2-torus the only known integrable example is that of a flow integrable for all energy levels. It has an integral linear in momenta and corresponds to a one parameter group preserving the Lagrangian function of the magnetic flow. In this paper the problem of integrability on a single energy level is considered. Then, in addition to the example mentioned above, a few other explicit examples with quadratic in momenta integrals can be constructed by means of the Maupertuis' principle. Recently we proved that such an integrability problem can be reduced to a remarkable semi-Hamiltonian system of quasi-linear PDEs and to the question of the existence of smooth periodic solutions for this system. Our main result of the present paper states that any Liouville metric with the zero magnetic field on the 2-torus can be analytically deformed to a Riemannian metric with a small magnetic field so that the magnetic geodesic flow on an energy level is integrable by means of an integral quadratic in momenta. [ABSTRACT FROM AUTHOR]

This paper presents the results of tests concerning the value of surface free energy on the basis of measurements of contact angle with measure liquids: distilled water and diiodomethane. The surface of steel-316L samples was modified in an ozone atmosphere, and the concentration of ozone and the conditioning time of the samples in the reaction chamber were changed. The results of tests concerning the measurements of the value of surface free energy were subject to analysis. Also analysed were the components of SFE: the polar and dispersive components. The obtained test results were analysed in statistical terms. The paper ends with conclusions. [ABSTRACT FROM AUTHOR]

In this paper, we recall the topological approach to quantum Hall effects. We note that, in the presence of a magnetic field, trajectories representing elements of the system's braid group are of cyclotron orbit type. In two-dimensional spaces, this leads to the restriction of the full braid group, π1(Ω)--loopless generators (exchanges of MN coordinates or classical particles) are unenforceable. As a result, the identification of a possible Hall-like state comes down to the identification of a possible subgroup of π1(Ω). The latter follows from the connection between the one-dimensional unitary representation of the system's braid group and particle statistics (unavoidable for any correlated state). In this work, we implement the topological approach to derive the lowest Landau-level pyramid of fillings. We point out that it contains all mysterious odddenominator filling factors--like 4/11, 4/13 or 6/17--not trivial to explain within the standard picture. We also introduce, explicitly, cyclotron subgroup generators for all derived fractions. Preliminary results on wave functions, supported by several Monte Carlo calculations, are presented. It is worth emphasizing that not all proposed many-body functions are purely antisymmetric--they, however, transform in agreement with the scalar representations of the system's braid group. The latter is enforced by standard quantization methods. [ABSTRACT FROM AUTHOR]

In this paper, several new protocols for the controlled remote state preparation (CRSP) by using the Brown state as the quantum channel are proposed. Firstly, we propose a CRSP protocol of an arbitrary two qubit state. Then, the CRSP protocol of an arbitrary three qubit state, which has rarely been considered by the previous papers, is investigated. The coefficients of the prepared states can be not only real, but also complex. To design these protocols, some useful and general measurement bases are constructed, which can greatly reduce the restrictions for the coefficients of the prepared states. The security analysis is provided in detail. Moreover, receiver's all recovery operations are summarized into a concise formula. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the initial boundary value problem of the nonlinear fourth-order dispersive-dissipative wave equation. By using the concavity method, we establish a blow-up result for certain solutions with arbitrary positive initial energy. [ABSTRACT FROM AUTHOR]

Owing to its large dipole, astrophysicists use carbon monosulfide (CS) as a tracer of molecular gas in the interstellar medium, often in regions where H2 is the most abundant collider. Predictions of the rovibrational energy levels of the weakly bound complex CS-H2 (not yet observed) and also of rate coefficients for rotational transitions of CS in collision with H2 should help to interpret the observed spectra. This paper deals with the first goal, i.e., the calculation of the rovibrational energy levels. A new four-dimensional intermolecular potential energy surface for the H2-CS complex is presented. Ab initio potential energy calculations were carried out at the coupled-cluster level with single and double excitations and a perturbative treatment of triple excitations, using a quadruple-zeta basis set and midbond functions. The potential energy surface was obtained by an analytic fit of the ab initio data. The equilibrium structure of the H2-CS complex is found to be linear with the carbon pointing toward H2 at the intermolecular separation of 8.6 ao. The corresponding well depth is -173 cm-1. The potential was used to calculate the rovibrational energy levels of the para-H2-CS and ortho-H2-CS complexes. The present work provides the first theoretical predictions of these levels. The calculated dissociation energies are found to be 35.9 cm-1 and 49.9 cm-1, respectively, for the para and ortho complexes. The second virial coefficient for the H2-CS pair has also been calculated for a large range of temperature. These results could be used to assign future experimental spectra and to check the accuracy of the potential energy surface. [ABSTRACT FROM AUTHOR]

In this paper, polyimide (PI) films were modified by using non-thermal plasma, which was generated by dielectric barrier discharge (DBD) in atmospheric air. Under repetitive impulse voltage, the lifetime of plasma treated PI films increases obviously, which reaches the maximum value of 16.8% higher than that of untreated PI films, obtained by 20 s' treatment. For further understanding lifetime improvement mechanism, energy level distribution of both electron-type and hole-type traps was calculated based on isothermal surface potential decay (ISPD) measurement. It is found that energy level of both shallow and deep traps decrease after treatment, reaching the lowest value for the films treated for 20 s. Lower energy for shallow trap is beneficial to charge dissipation, so that local electrical field would be mitigated. Furthermore, lower energy for deep trap results in less amount of trapped surface charges. Thus, surface PD intensity would be suppressed, ending up with longer lifetime. Analysis of chemical bonding structure reveals that active groups rich in oxygen and nitrogen were introduced into the near-surface region of plasma treated sample, which are responsible for corresponding change of trap energy level distribution. However, in order to prolong lifetime effectively, plasma treating time must to be controlled in an appropriate range. [ABSTRACT FROM AUTHOR]

In this paper, we propose coarse-grained single-site (CGSS), wall-CO2, and CO2-CO2 interaction potential models to study the structure of carbon dioxide under confinement. The CGSS potentials are used in an empirical potential based quasi-continuum theory, EQT, to compute the center-of-mass density and potential profiles of CO2 confined inside different size graphite slit pores. Results obtained from EQT are compared with those obtained from all-atom molecular dynamics (AA-MD) simulations, and are found to be in good agreement with each other. Though these CGSS interaction potentials are primarily developed and parameterized for EQT, they are also used to perform coarse-grained molecular dynamics (CG-MD) simulations. The results obtained from CG-MD simulations are also found to be in reasonable agreement with AA-MD simulation results. [ABSTRACT FROM AUTHOR]

In this paper, we introduce an algebraic approach to electronic structure calculations. Our approach constructs a Jordan algebra based on the second-quantized electronic Hamiltonian. From the structure factor of this algebra, we show that we can calculate the energy of the ground electronic state of the Hamiltonian operator. We apply our method to several generalized Hubbard models and show that we can usually obtain a significant fraction of the correlation energy for low-to-moderate values of the electronic repulsion parameter while still retaining the O(L3) scaling of the Hartree-Fock algorithm. This surprising result, along with several other observations, suggests that our algebraic approach represents a new paradigm for electronic structure calculations which opens up many new directions for research. [ABSTRACT FROM AUTHOR]

In this paper we propose and test a method for computing numerically exact vibrational energy levels of a molecule with six atoms. We use a pruned product basis, a non-product quadrature, the Lanczos algorithm, and the exact normal-coordinate kinetic energy operator (KEO) with the πtμπ term. The Lanczos algorithm is applied to a Hamiltonian with a KEO for which μ is evaluated at equilibrium. Eigenvalues and eigenvectors obtained from this calculation are used as a basis to obtain the final energy levels. The quadrature scheme is designed, so that integrals for the most important terms in the potential will be exact. The procedure is tested on C2H4. All 12 coordinates are treated explicitly. We need only ∼1.52 × 108 quadrature points. A product Gauss grid with which one could calculate the same energy levels has at least 5.67 × 1013 points. [ABSTRACT FROM AUTHOR]

A new approach avoiding double (two-step) diagonalization is proposed to deal with internal rotation. The development of this method was stimulated by the jet-cooled high resolution spectrum of the vibrationless Ã←X transition of the deuterated species of the methyl peroxy radical. This spectrum, originally analyzed with a rigid rotor Hamiltonian including spin-rotation but neglecting internal rotation, has been revisited in the previous paper (P. Dupré, J. Chem. Phys. 134, 244308 (2011)) and a determinable yaw of the molecular principal axes of inertia about the c-axis (axis-switching) during the electronic transition was established. The spectral resolution of the jet-cooled data of the vibrationless transition (∼7355 - 7390 cm-1) does not allow the observation of splitting due to internal rotation of the methyl top, but when these data are combined with the low resolution room temperature data (∼7200 - 8000 cm-1) accurate fits or simulations of the two sets of data are possible. A recent study of the room temperature data has been reported in this journal (G. M. P. Just et al., J. Chem. Phys. 127, 044310 (2007)) showing evidence of the internal rotation coupling by analyzing the intensity of the torsional mode energy progression. That investigation combined ab initio quantum chemistry calculations and the rho-axis-method (RAM) to model the internal rotation. Here, a comparison of full spectral intensity analyses based on both the usual RAM and on the new approach requiring a single-diagonalization principal-axis-method is presented. The comparison favors the single-diagonalization approach. Axis-switching and spin-rotation coupling are incorporated in the analysis, in which the use of the principal axes of inertia is maintained. Symmetries, energy levels, and advantages are carefully discussed for all methods. [ABSTRACT FROM AUTHOR]

Internal conversion is an inherently quantum mechanical process. To date, 'on the fly' computation of internal conversion rates is limited to harmonic approximations, which would seem to be especially unsuitable, given that the typical transition to the ground electronic state occurs at energies which are far from the harmonic limit. It is thus of interest to study the applicability of the semiclassial initial value representation (SCIVR) approach which is in principle amenable to on the fly studies even with 'many' degrees of freedom. In this paper we study the applicability of the Herman-Kluk (HK) SCIVR to a model system with two coupled and anharmonic degrees of freedom. We find that (a) the HK SCIVR is a good approximation to the exact quantum dynamics; (b) computation of the first order correction to the HK-SCIVR approximation corroborates the accuracy; (c) by studying a large parameter range, we find that the harmonic approximation is mostly unsatisfactory; and (d) for the specific model used, the coupling between the modes was found to be relatively unimportant. These results imply that the HK-SCIVR methodology is a good candidate for on the fly studies of internal conversion processes of 'large' molecules. [ABSTRACT FROM AUTHOR]

Thermal gratings are a well known feature in one-dimensional (i.e., single excitation) transient-grating spectroscopy. This paper presents theory and experiments for thermal gratings in multiple dimensions (i.e., with many excitations). The theory of thermal gratings is extended to an arbitrary number of dimensions using an incoherent Hilbert-space formalism. Interference between Hilbert-space pathways makes it impossible for a thermal grating to propagate across multiple time intervals. The only surviving signal is a hybrid-a population grating between excitations and a thermal grating between the final excitation and the probe. This theory is tested on auramine O in methanol (1D) and in an ionic liquid (3-butyl-1-methylimidazolium hexafluorophosphate) (1D and 2D). In methanol, the ground-state recovery and thermal-grating signals are well separated in time; in the ionic liquid, they are not. Using the results of the theory, accurate subtraction of the thermal-grating signal is possible, extending the useful time range of the experiments. Both the comparison to the theory and the subtraction of the thermal-grating signal are dependent on accurate measurements of the time-dependent phase in these systems. Models are proposed to account for the time-dependent phase. Beer's law is generalized to multidimensional grating spectroscopy. This law provides conventions for consistently comparing the absolute phases and magnitudes between grating and nongrating experiments and between experiments of differing dimensionality. [ABSTRACT FROM AUTHOR]

Persistent quantum control (PQC) aims to maintain an observable objective value over a period of time following the action of an applied field. This paper assesses the feasibility of achieving PQC for arbitrary finite-level systems and observables. The analysis is carried out independent of the particular method used for state preparation. The PQC behavior is optimized over the set of physically accessible prepared states for both open and closed systems. The quality of observable value persistence in the postcontrol period was found to vary with the required duration of persistence, the system temperature, the chosen observable operator, and the energy levels of the system. The alignment of a rigid diatomic rotor is studied as a model system. The theoretical estimates of PQC behavior are encouraging and suggest feasible exploration in the laboratory using currently available technology. [ABSTRACT FROM AUTHOR]

The intermediate band (IB) concept is regarded as a way of exceeding the Shockley-Queisser efficiency limit through a more efficient use of the solar spectrum. Quantum dots (QDs) have been proposed to achieve a practical implementation of this concept. So far, only few QD material systems, such as In(Ga)As/GaAs and related compounds, have been tested experimentally giving rise to two important conclusions: on the one hand, the verification of the concept fundamentals and on the other hand, the need to seek new QD candidate materials in order to produce high efficiency devices. As regards the latter, in this paper we present an analytical model to assess the potential of QD IB solar cells (IBSCs) consisting of the following steps: (1) calculation of the heterojunction band alignment taking material strain into account, (2) calculation of the QD confined energy levels constituting the IB, and (3) calculation of the efficiency limits in the detailed balance realm and optimization of the QD systems in terms of QD size and material composition. The search criteria are reviewed and three QD systems (InAs/AlxGa1-xAs, InAs1-yNy/AlAsxSb1-x, and InAs1-zNz/Alx[GayIn1-y]1-xP) are identified together with their optimum QD sizes. Efficiencies of over 60% are calculated at maximum light concentration. [ABSTRACT FROM AUTHOR]

A pair of chemically powered self-propelled nanodimers can exist in a variety of bound and unbound states after undergoing a collision. In addition to independently moving unbound dimers, bound Brownian dimer pairs, whose center-of-mass exhibits diffusive motion, self-propelled moving dimer pairs with directed motion, and bound rotating dimer pairs, were observed. The bound pairs arise from a solvent depletion interaction, which depends on the nonequilibrium concentration field in the vicinity of dimers. The phase diagram reported in the paper shows regions in monomer interaction energy-diameter plane where these bound and unbound states are found. Particle-based simulations and analytical calculations are used to provide insight into the nature of interaction between dimers that gives rise to the observed bound states. [ABSTRACT FROM AUTHOR]

In this paper we present the theory and implementation of the symmetry-adapted cluster (SAC) and symmetry-adapted cluster-configuration interaction (SAC-CI) method, including the solvent effect, using the polarizable continuum model (PCM). The PCM and SAC/SAC-CI were consistently combined in terms of the energy functional formalism. The excitation energies were calculated by means of the state-specific approach, the advantage of which over the linear-response approach has been shown. The single-point energy calculation and its analytical energy derivatives are presented and implemented, where the free-energy and its derivatives are evaluated because of the presence of solute-solvent interactions. We have applied this method to s-trans-acrolein and metylenecyclopropene of their electronic excitation in solution. The molecular geometries in the ground and excited states were optimized in vacuum and in solution, and both the vertical and adiabatic excitations were studied. The PCM-SAC/SAC-CI reproduced the known trend of the solvent effect on the vertical excitation energies but the shift values were underestimated. The excited state geometry in planar and nonplanar conformations was investigated. The importance of using state-specific methods was shown for the solvent effect on the optimized geometry in the excited state. The mechanism of the solvent effect is discussed in terms of the Mulliken charges and electronic dipole moment. [ABSTRACT FROM AUTHOR]

In the first paper of this series, a very accurate ab initio potential energy curve of the 3Σg- ground state of O2 has been determined in the approximation that all valence shell electron correlations were calculated at the complete basis set limit. In the present study, the corrections arising from core electron correlations and relativity effects, viz., spin-orbit coupling and scalar relativity, are determined and added to the potential energy curve. From the 24 points calculated on this curve, an analytical expression in terms of even-tempered Gaussian functions is determined and, from it, the vibrational and rotational energy levels are calculated by means of the discrete variable representation. We find 42 vibrational levels. Experimental data (from the Schumann–Runge band system) only yield the lowest 36 levels due to significant reduction in the transition intensities of higher levels. For the 35 term values G(v), the mean absolute deviation between theoretical and experimental data is 12.8 cm-1. The dissociation energy with respect to the lowest vibrational energy is calculated within 25 cm-1 of the experimental value of 41 268.2±3 cm-1. The theoretical crossing between the 3Σg- state and the 1Σg+ state is found to occur at 2.22 Å and the spin-orbit coupling in this region is analyzed. [ABSTRACT FROM AUTHOR]