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In water-guided laser technology, the stability of water jets is crucial to ensure the efficient transmission of laser energy. However, the thermal effects generated when high-power lasers are coupled with water jets are bound to impact the stability of the water jets, thus becoming a critical issue that restricts the development of high-power water-guided laser technology. In addressing this issue, this paper establishes a temperature model for coupling high-power lasers with water jets. Subsequently, with validation of the model's effectiveness through experimental data, simulations are conducted to analyze the temperature distribution within the water jet. During the simulation process, lasers with different parameters were coupled with water jets to analyze the temperature variation law of the water jets. Additionally, the maximum laser power coupled with water jets of different lengths was solved. Based on the calculated temperature values of the water jet, simulate the evolution of its profile over time when it has an initial temperature gradient. Simultaneously, perform a three-dimensional reconstruction of the obtained perturbed profile and conduct ray tracing to analyze the laser's transmission losses within the perturbed profile. Finally, high-speed cameras are utilized to capture the profile of the water jet, validating the laser-induced fragmentation behavior in the water jet. The research findings will provide a significant reference value for selecting laser parameters and controlling thermal effects in water-guided high-power technology. [ABSTRACT FROM AUTHOR]

This Tutorial article focuses on magnetic phenomena and material systems that have gained significant importance since the original development of mumax3, but are challenging to simulate for users who rely solely on the originally provided examples. Alongside the physical background, we provide hands-on examples of advanced magnetic systems, including detailed explanations of complete mumax3 input files (13 in total, often showing different ways to achieve things), and highlighting potential pitfalls where applicable. Specifically, we explore two approaches to incorporate spin–orbit torques in mumax simulations, considering the trade-off between versatility and speed. We also examine complex multilayer material stacks, including synthetic antiferromagnets, demonstrating different implementation methods that again vary in speed, versatility, and realism. A key criterion for selecting the optimal simulation strategy is its suitability for modeling systems where the magnetization varies significantly in the third dimension. The material covered in this Tutorial paper includes content developed for the mumax3 workshop presented during the summer of 2020 within the context of the IEEE online spintronics seminar, along with additional new topics. Throughout the explanations, we ensure broad applicability beyond specific examples. [ABSTRACT FROM AUTHOR]

This paper provides a numerical analysis of the topological valley kink states along both zigzag and armchair domain walls of a dielectric two-dimensional photonic crystal (PC), considering the photonic energy band folding mechanism. By engineering the side length of triangular holes in a honeycomb PC, we created inequivalent valleys in the momentum space. We utilized two adjacent valley PCs with inverted structures to induce a topological transition of the TE mode energy band as it crossed the interface. Further research into the projected energy bands along both zigzag and armchair directions revealed that topologically protected valley kink states can be supported by both configurations. The zigzag interface enabled valley waveguides to transport chiral optical fields at the 0°, 60°, and 120° bending angles, while maintaining their backscattering immune properties. The armchair interface, on the other hand, supported the straight propagation. By combining both armchair and zigzag interfaces, the valley waveguide can facilitate bending propagation at 90° and 180°, while also enabling the equal splitting of chiral fields at the intersection between these two interfaces. Our analyzation can be helpful to improve the applications of valley waveguides in integrated photonics. [ABSTRACT FROM AUTHOR]

Reactive burn models for heterogeneous energetic materials (EMs) must account for chemistry as well as microstructure to predict shock-to-detonation transition (SDT). Upon shock loading, the collapse of individual voids leads to ignition of hotspots, which then grow and interact to consume the surrounding material. The sub-grid dynamics of shock-void interactions and hotspot development are transmitted to macro-scale SDT calculations in the form of a global reactive "burn model." This paper presents a physically evocative model, called meso-informed sub-grid source terms for energy localization (MISSEL), to close the macro-scale governing equations for calculating SDT. The model parameters are explicitly related to four measurable physical quantities: two depending on the microstructure (the porosity ϕ and average pore size D ¯ v o i d ), one depending on shock–microstructure interaction (the fraction of critical voids ξ c r ), and the other depending on the chemistry (the burn front velocity V h s ). These quantities are individually quantifiable using a small number of rather inexpensive meso-scale simulations. As constructed, the model overcomes the following problems that hinder the development of meso-informed burn models: (1) the opacity of more sophisticated surrogate/machine-learning approaches for bridging meso- and macro-scales, (2) the rather large number of high-resolution mesoscale simulations necessary to train machine-learning algorithms, and (3) the need for calibration of many free parameters that appear in phenomenological burn models. The model is tested against experimental data on James curves for a specific class of pressed 1,3,5,7-tetranitro-1,3,5,7-tetrazoctane materials. The simple, evocative, and fast-to-construct MISSEL model suggests a route to develop frameworks for physics-informed, simulation-derived meso-informed burn models. [ABSTRACT FROM AUTHOR]

Due to the importance of supercapacitors in electronic storage devices, improving their efficiency is one of the topics that has attracted the attention of many researchers. Choosing the proper electrolyte for supercapacitors is one of the most significant factors affecting supercapacitors' performance. In the present paper, we compare liquid electrolytes (ionic liquid electrolytes) and solid electrolytes (polymer electrolytes) by molecular dynamics simulation to summarize their pros and cons. We consider polymer electrolytes in linear and network configurations. The results show that although ionic liquid-based supercapacitors have a larger differential capacitance since they have a smaller operation voltage, the energy stored is less than polymer electrolyte-based supercapacitors. Also, our investigations indicate that polymer electrolyte-based supercapacitors have more mechanical stability. Therefore, they can be considered a very suitable alternative to liquid electrolyte-based supercapacitors since they do not have known liquid electrolyte problems and display better performance. [ABSTRACT FROM AUTHOR]

The plasma instability of two-dimensional electron gas (2DEG) is a crucial physical mechanism for generating terahertz radiation in field-effect transistors, especially in high electron mobility transistors (HEMTs). In this paper, we have proposed a new semi-analytical and semi-numerical method to deal with oscillation problems of any nonuniform 2DEG plasma, especially considering the steady-state distribution, which can be calculated and analyzed more quickly than only using numerical calculation. By constructing a wave equation, using the auxiliary function and Wentzel–Kramers–Brillouin approximation method, the wave vector of the plasma wave is obtained. On this basis, combined with the Dyakonov–Shur instability's boundary conditions, the oscillation frequency, the wave amplitude increment, and their correction caused by the nonuniformity can be obtained by numerical calculation. Furthermore, the analytical solution is obtained under reasonable approximate conditions for the linear distribution of electron concentration. It is proved that the electron concentration gradient in the channel will not only attenuate the wave increment but also decrease the plasmonic frequency in the case of linear distribution. Moreover, we get the reasons for the above conclusions through theoretical derivation. We also investigate the effects of various device parameters on attenuation, such as gate length, electron mobility, and voltage, which may explain the difference between the actual and theoretical values in HEMTs and provide new guidance for device design. [ABSTRACT FROM AUTHOR]

PVD technologies, including vacuum arc evaporation and DC-magnetron sputtering, have been utilized in industrial settings since the early 1980s for depositing protective coatings. These coatings encompass a range of materials such as metal nitrides, carbonitrides, oxides, oxynitrides, and DLC, serving diverse applications such as cutting and forming tools, automotive components, and decoration. Vacuum arc evaporation generates a highly energized and ionized particle flux toward the substrate, while "classical" gas-ion-dominated direct current magnetron sputtering (DCMS) has limitations in generating ionized and energetic species of the sputtered target material. The development of High-Power Impulse Magnetron Sputtering (HiPIMS) has exhibited significant potential in addressing DCMS's limitations by enabling the production of highly energetic particles. This innovation, with its industrial applicability for protective coatings, was introduced around 2010. This paper aims to provide an industrial perspective on HiPIMS, serving as a guide for scientists and engineers in comprehending and implementing HiPIMS solutions. It covers historical context and fundamental characteristics. Basic features as well as state-of-the-art configurations of PVD systems are also described. Graphical representations of experimental results illustrate HiPIMS features, including operational modes, deposition rate effects, thickness uniformity, and sustainability, particularly in terms of energy efficiency. The discussion focuses on the application prospects, advantages, and constraints of industrially applied HiPIMS protective coatings, emphasizing cutting and forming tools, within the context of the findings presented. [ABSTRACT FROM AUTHOR]

Dielectric energy storage capacitors offer great potential in pulsed power devices due to the high power density and fast charging-discharging rate. Designing a host material with high field-induced polarization is of importance for developing dielectric energy storage materials via further composition modulation. In this paper, we compare the microstructure, dielectric, and ferroelectric properties as well as the energy storage performance of samples K1/2Bi1/2TiO3(KBT), 75KBT-25BiFeO3 (KBTF25), and 88KBT-12Bi0.85Nd0.15FeO3 (KBNTF12) in detail. It is found that, among three samples, sample KBNTF12 possesses the most complex local structure coexisting of a four-distortions with different polarities; meanwhile, sample KBNTF12 behaves as a strong relaxor, thus giving a high field-induced polarization. Besides, sample KBNTF12 realizes the highest electric breakdown strength Eb among three samples, which is resorted to the highest resistivity of grain boundary. Highest ΔP and Eb of sample KBNTF12 among three samples render it achieve ultrahigh stored energy density Ws of 6.94 J/cm3, high recoverable energy density Wr of 5.23 J/cm3, and high efficiency η of 75.4%. Our work suggests that 88KBT-12BNF binary composition be an optimal candidate for dielectric energy storage ceramics. [ABSTRACT FROM AUTHOR]

This paper presents a novel physics-based analytical model for the injection recombination current in micro-light emitting diodes (μLEDs) with multiple quantum wells (MQWs), specifically excluding trap-assisted tunneling contributions at low forward voltages. The model simplifies the complex MQW structure by representing MQWs as a single equivalent quantum well (EQW). The μLED current is attributed to the recombination of injected holes and electrons within this EQW. Key parameters of the model encompass the EQW's position within the depletion region, hole diffusion coefficient, series resistance, and thermal resistance of the device. Experimental validation of the model is performed using current–voltage characteristics obtained from InGaN/GaN QW μLEDs. [ABSTRACT FROM AUTHOR]

The deployment of fifth-generation mobile network (5G), beyond 5G and sixth-generation mobile network platforms encounters challenges of blockage, interference, and path loss in radio mobile environments. Metasurfaces provide a promising solution to address these limitations. In this paper, we present a methodology for developing ultrathin flexible metasurface-based frequency selective surfaces (FSSs). Our approach combines thermal evaporation for metallic thin films with a macroscopic metasurface mask (something analogous to screen-printing but using thermal evaporation instead of inks). As a proof of concept, we fabricate a sub-6 GHz metasurface-based FSS using gold deposition on a flexible polyethylene terephthalate substrate. Experimental results are validated through numerical full-wave simulations using COMSOL Multiphysics and equivalent-circuit model simulations. The metasurface operates within the primary frequency band utilized in 5G networks (3–5 GHz), indicating its potential applicability across a wide range of flexible, conformal, and wearable devices. The fabricated FSS can be installed on surfaces of any shape, such as flat or curved windows, as well as on walls or other external surfaces. This methodology offers practical solutions for wireless communications and enhancing signal transmission in diverse environments. [ABSTRACT FROM AUTHOR]

Strain-related piezoelectric polarization is detrimental to the radiative recombination efficiency for InGaN-based long wavelength micro-LEDs. In this paper, partial strain relaxation of InGaN multiple quantum wells (MQWs) on the wafer scale has been demonstrated by adopting a partially relaxed InGaN superlattice (SL) as the pseudo-substrate. Such a pseudo-substrate was obtained through an electro-chemical etching method, in which a sub-surface InGaN/InGaN superlattice was etched via threading dislocations acting as etching channels. The degree of strain relaxation in MQWs was studied by x-ray reciprocal space mapping, which shows an increase of the in-plane lattice constant with the increase of etching voltage used in fabricating the pseudo-substrate. The reduced strain in the InGaN SL pseudo-substrate was demonstrated to be transferable to InGaN MQWs grown on top of it, and the engineering of the degree of strain relaxation via porosification was achieved. The highest relaxation degree of 44.7% was achieved in the sample with the porous InGaN SL template etched under the highest etching voltage. Morphological and structural properties of partially relaxed InGaN MQWs samples were investigated with the combination of atomic force and transmission electron microscopy. The increased porosity of the InGaN SL template and the newly formed small V-pits during QW growth are suggested as possible origins for the increased strain relaxation of InGaN MQWs. [ABSTRACT FROM AUTHOR]

This paper investigates near-interfacial charge trapping effects in graphene field-effect transistors with high-K gate dielectrics. Experimental and model-based analysis elucidates the impact of trapped charge on the transport properties of graphene. Landauer formalism is applied to correlate trapping-enhanced charged impurity scattering to degradation in conductivity and mobility. The analysis shows a significant reduction in conductivity and mobility with a transition toward the dominance of charge impurity scattering as evidenced by their dependence on the sheet carrier density. Moreover, we quantify the impact of trapped charge buildup on the carrier backscattering mean free path associated with charged impurities. This work provides new insights into the impact of charge trapping toward the development of logic, memory, and neuromorphic devices based on graphene and other low-dimensional materials and ultrascaled high-K dielectrics. [ABSTRACT FROM AUTHOR]

In the pursuit of developing high-performance low-dimensional spintronic devices, two-dimensional van der Waals heterostructures comprising non-magnetic nitride and ferromagnetic materials have emerged as a crucial area of investigation. This paper proposes a novel structure that employs hexagonal two-dimensional semiconductor GaN flanked by two half-metallic two-dimensional CrN layers. The stability of the proposed structure is verified via first-principles calculations, which indicate good thermodynamic and magnetic stability. The transport characteristics of electrons in the structure are analyzed through the Band structures and density of states. Specifically, the study examines the spin polarizability of parallel and anti-parallel magnetic configurations of the CrN/GaN/CrN vdW heterostructure, and the results demonstrate a significant spin valve effect. Overall, the study establishes the potential of the CrN/GaN/CrN vdW heterostructure as a candidate for the development of innovative spintronic devices. [ABSTRACT FROM AUTHOR]

In the paper, a metasurface is investigated, the unit cell of which consists of two resonators. We show that the breaking of the axial symmetry of the unit cell in such a structure leads to the appearance of two Fano resonances instead of one that is characteristic of the symmetric unit cell. The two resonances are different, one of which is symmetric and the other is asymmetric. This is confirmed by calculating the phases of currents in the adjacent resonators. Modeling results are confirmed by experimental investigation of the metasurface spectrum in a microwave frequency range showing two resonances measured experimentally. A detailed study of the currents flowing in the adjacent resonators of the unit cell demonstrates that currents at the Fano resonance dips flow either in phase or in antiphase with respect to the external electric field, whereas in peaks this difference is π /2. This confirms the interference nature of the Fano effect. [ABSTRACT FROM AUTHOR]

Models attempting an analytical description of free-electron laser (FEL) devices have been proposed in the past. They provided interesting results, leading either to a deeper understanding of the FEL dynamics and to semi-analytical formulae, useful for the preliminary design of self amplified spontaneous emission and oscillator FELs. Most of these models work well until the level of mild saturation. In this paper, we comment on the so-called logistic model and a more recent analysis describing the FEL evolution in terms of Jacobi elliptic functions. Both models are shown to be suited to describe the evolution from the low signal to the onset of saturation. We attempt therefore an extension of these theoretical formulations using a delayed logistic model, capable of including characteristic features like the post saturation power oscillations. [ABSTRACT FROM AUTHOR]

Recent optical time-resolved experiments on single supported nano-objects (gold nanodisks with various diameter over thickness ratios) have demonstrated a marked enhancement of their vibrational quality factors for specific nano-object morphologies, resulting from the near-suppression of radiative vibrational damping associated with the emission of acoustic waves in the nano-object environment. This paper clarifies the origin of this phenomenon, which is ascribed to the creation of a "quasi-bound state in the continuum" vibrational mode by radiative coupling between two nano-object modes whose frequencies become close for specific nano-object shapes. The symmetry breaking induced by the presence of a substrate, which limits nanodisk acoustic emission to a half-space, is shown to play an essential role in enabling such radiative coupling. The impact of the acoustic mismatch between the nano-object and the substrate is explored, and it is shown that a moderate acoustic mismatch can still enable the creation of near-localized vibrational modes with high radiative quality factors, while allowing radiative coupling effects to occur over a broad range of nano-object geometries. Although this paper focuses on the situation of a substrate-supported gold nanodisk, which has already been the object of experimental investigations, the effects that it describes are general and constitute a promising approach to enhance the vibrational quality factors of nano-objects. [ABSTRACT FROM AUTHOR]

Digital fringe projection profilometry based on phase-shifting technology is a reliable method for complex shape measurement, and the phase is one of the most important factors affecting measurement accuracy. The calculation of the absolute phase depends on the calculation of the wrapped phase and encoding technology. In this paper, a technique of obtaining the absolute phase of multi-frequency heterodyne fringe images using the Hilbert transform is presented. Since the wrapped phase can be calculated from only one fringe image of each frequency, the method does not need phase-shifting. The absolute phase can be obtained from the wrapped phase by applying the heterodyne method. The measurement time and computational complexity are dramatically reduced, the measurement efficiency is greatly improved, and this benefit from the number of images is greatly reduced. The experimental results show that the method presented in this paper performs well in the application, and the accuracy is no different from that of the phase-shifting method while the efficiency is greatly improved. [ABSTRACT FROM AUTHOR]

Two-dimensional layered materials, in general, and transition metal dichalcogenides, in particular, are promising as future device materials. Vanadium based dichalcogenides, i.e., VX2 (X = S, Se, and Te) are special in the class for showing a wide range of intriguing properties. Depending on the structural phases, VX2 can be metallic or semiconducting. The T-phase, i.e., the metallic one, is well known to host some exotic electronic properties like the charge density wave, anomalous Hall effect, ferromagnetism, etc., having strong bearing as an electronic device material. The H-phase, on the other hand, is also predicted to show ferromagnetism. The materials show properties strongly dependent on their physical dimensionality, a clear manifestation of quantum confinement effects. Several experimental attempts successfully demonstrated chemical and bio-medical applications also of this class of materials. Moreover, the heterostructures formed by VX2 with other electronically dissimilar materials could bring more variation in their existing properties. Therefore, the study of VX2 materials provides a fertile ground to explore several fascinating physical phenomena and their possibilities in future applications. Here, in the present paper, we have tried to review the current scenario in this particular field by highlighting some recent key findings. The paper is aimed at providing some insight into the recent theoretical and experimental achievements in this direction, especially in the context of electronic and magnetic properties in their lower physical dimensionality. This could furnish a comprehensive guiding tour toward exploration in the journey through VX2 materials. [ABSTRACT FROM AUTHOR]

In this paper, we study the electromechanical behaviors of a charge-controlled dielectric film that may encounter symmetry-breaking instability. With electric charges and the radial dead load, a circular film would gradually expand its area and become a large circular film; however, it will deform into an elliptical film when electromechanical loads increase to the threshold. This symmetry-breaking instability brings the change of shape and makes the dielectric film achieve large electro-actuation and high stored energy. Since the functionality of the dielectric devices is also limited by the electric breakdown, we give the phase diagram to show the competition between the symmetry-breaking instability and the electric breakdown in detail. This paper is desirable to further harness the symmetry-breaking instability for improving functionalities of actuators and harvesters. [ABSTRACT FROM AUTHOR]

In this paper, we present the physics and design-space exploration of a novel pulse compression photoconductive switch (PCPS) using semi-insulating gallium arsenide (GaAs) operating in the negative differential mobility (NDM) regime of electron transport. We systematically quantify the relationship between the PCPS performance and various design options, including contact separation, laser energy and placement, and trap dynamics. Specifically, we report the full-width at half-maximum and the peak output current generated by the PCPS as a function of applied electrical and optical bias. We discuss the optimal spacing between the electrodes and the distance of the laser spot to the anode to achieve higher electron confinement and superior radio-frequency (RF) metrics. Reducing the laser energy is important to prevent the appearance of secondary peaks due to diffusive transport, but there exists a trade-off between the bandwidth and the maximum current of the PCPS. We also compare the PCPS response with and without trap dynamics and find that the electrostatic screening from the trap-induced space charge is time-independent when the trapping time constant is set larger than the recombination lifetime. Overall, trap dynamics are detrimental to performance, unless the compensation doping scheme to achieve semi-insulating GaAs is carefully selected. Results presented in this paper can be used by experimentalists to fine-tune the PCPS design parameters to meet the specifications of various RF applications. Moreover, our results will provide a strong theoretical basis to the measurements of PCPS devices using GaAs and other NDM materials under investigation. [ABSTRACT FROM AUTHOR]

This document is an erratum for an article titled "Advances in superconductor quantum and thermal detectors for analytical instruments" published in the Journal of Applied Physics. The erratum points out typographical errors, spelling mistakes, and an improper description of binding energy in the original article. It provides corrections for equations (2) and (4) on page 6 and clarifies that the word "biding" should be read as "binding" in multiple instances throughout the paper. Additionally, a sentence containing a physical error is replaced with a corrected version. The erratum states that these errors do not affect the rest of the paper. [Extracted from the article]

This document is an erratum for a paper titled "Dielectric conductivity and microwave heating behavior of NiO at high temperature" published in the Journal of Applied Physics. The erratum corrects Equation (8) in the original paper and provides the correct version. It also includes additional sentences that clarify the frequency dependence of the conductivity and the validity of the conclusion. Finally, Equation (9) is replaced with the correct version. The erratum is authored by Noboru Yoshikawa and Haruto Sato. [Extracted from the article]

This paper analyses the behavioral features of ohmic contacts under the conditions of traditional isothermal annealing. The purpose of this paper is to study the value change of the semiconductor contact resistance when applying electric current pulses of different powers. For the experiments, structures were formed of metal-sublayer-semiconductor wafer Al–(Ti, Ni, Mo)–Si. The quality control of the deposited films was carried out microscopically by the four-probe method. The presented results indicate the solid-phase interaction of components during diffusion annealing Si–Me–Al thin-film systems. This rearrangement of atoms, which occurs with grain-boundary diffusion, significantly affects the electrical and thermal characteristics of the formed contacts. The novelty of the paper is that the optimal parameters of a rectangular current pulse were selected, which made it possible to reduce the value of the transition resistance by 1.6 times. [ABSTRACT FROM AUTHOR]

A pure bending semiconductor beam that exhibits a non-homogeneous cross section variation enhanced flexoelectric coupling effect is investigated in this paper from the point of view of theoretical analysis and numerical calculations. According to the macroscopic theory of flexoelectric semiconductors, a one-dimensional bending model for a simple-supported beam with variable cross section is developed. The semi-analytical method, which is composed of cosine series and supplementary functions, is introduced to solve the partial differential equations with variable coefficients. Before the analysis, the convergence and correctness of the semi-analytical method are demonstrated systematically. The calculated results show that both the electric potential and the charge carrier distribute non-homogeneously in the entire beam under a pair of symmetric bending moments. It is revealed that more carriers, a larger electric potential, and more charges tend to concentrate in the zone near the ends. After introducing a dimensionless carrier density, this paper systematically investigates the non-homogeneous cross section variation effect on the flexoelectric coupling for charge carrier redistribution. It is indicated that more perturbation carriers in a non-uniform beam are produced by the enhanced flexoelectric coupling. The demonstration of this concept could be potential guidance for designing new semiconductor devices. [ABSTRACT FROM AUTHOR]

Piezotronic devices have attracted a great deal of attention due to their potential applications in self-powered tactile sensing, nano-device memory, human-electronic interface, etc. As the size of piezotronic devices shrinks, some interesting quantum effects begin to appear. In this paper, we establish a theory oriented to the engineering application of piezoelectric semiconductors, called quantum-corrected phenomenological (QCP) theory, by coupling the density-gradient theory and the linear piezoelectricity theory through Gauss's law. For numerical verification, we specifically studied the electromechanical behaviors in GaN/AlGaN heterostructure quantum wells (QWs) with both infinite and finite barrier height. The results of electron density, electric potential, and quantum potential are provided, and their dependence on the doping density, the applied stress, and the Al mole fraction is investigated. Some interesting quantum effects are revealed, and their influencing mechanisms are well investigated from a macroscopic perspective. Not only do the conclusions drawn in this paper enrich the fundamental understanding of the piezotronic effect in a QW structure, but also the proposed QCP theory can serve as a valuable tool for future device engineering. [ABSTRACT FROM AUTHOR]

The author comments on the article "Advanced mechanical properties of graphene paper (GP)," which was published in a 2011 issue. He states that the authors of the study have concluded that field emission scanning electron microscope (FE-SEM) observation showed that the structure of GP is similar to the interlocked tiles. He mentions that the significant finding is that heat treated GP reveals very high hardness and yielding length.

The article discusses the highlights of the 11th International Surface X-ray and Neutron Scattering (SXNS-11) Conference that took place at the Northwestern University (NU) campus in Evanston, Illinois from July 13-17, 2010. The conference, which was hosted by the NU Materials Research Science and Engineering Center, has gathered 164 delegates from 16 countries. Information on papers presented at the conference are presented.

An introduction to the topics discussed within the publication is presented, which are selected papers from the International Conference on Flexible and Printed Electronics held in Jeju Island, Korea on November 11 to 13, 2009, including articles on the difficulties posed by printing methods over ink materials to flexible and printed devices.

The article discusses conference papers on topics related to physics which were featured at the the Fourth International Conference on Multiscale Materials Modeling, which was held October 27-31 in 2008 in Tallahassee, Florida.

A preface to the Special Topic section of selected papers for the 20th International Symposium on Integrated Ferroelectrics is presented.

A preface to "Plenary and Invited Papers" from the 28th International Conference on the Physics of Semiconductors, Vienna, Austria, 2006 is presented.

A preface to the special issue of the "Journal of Applied Physics," which focused on piezoresponse force microscopy and nanoscale phenomena in polar materials, is presented.

Understanding the properties of N-implanted β-Ga2O3 is fundamental for the optimization of doping and isolation structures based on gallium oxide. This paper reports an extensive analysis of the impact of thermal annealing on the concentration and properties of deep levels in N-implanted β-Ga2O3 Schottky barrier diodes by means of capacitance isothermal transient spectroscopy. Samples with annealing temperatures from 800 to 1200 °C were considered. The original results presented in this paper demonstrate the following: (a) The instability of current–voltage characteristics detected for all the samples under test can be attributed to the presence of three electron traps with activation energies of 0.6, 0.7, and 1 eV, consistent with previous reports in β-Ga2O3. (b) The detected traps are not the nitrogen level but intrinsic defects whose concentration is increased by the implantation process. (c) The concentration of deep levels decreases as the annealing temperature increases, demonstrating that the annealing process can effectively restore the quality of the material while keeping the conductivity decrease related to the presence of the nitrogen. Finally, (d) we demonstrate that the residual leakage and the turn-on voltage shift are correlated with the Arrhenius signature of the detected deep levels. An interpretation is proposed to explain the measurement results. [ABSTRACT FROM AUTHOR]