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Planar polycrystalline laser waveguides with the structure YAG/Yb:YAG/YAG were produced by ceramic processing. Transparent ceramics represent a valid alternative to single crystals as the flexibility of the ceramic process paves the way to new application opportunities. The implementation of different ceramic shaping techniques allows the production of complex or multicomponent (composite) structures that are generally difficult or about impossible to obtain with single crystals. A practical example are the planar structures presented here, characterized by a strict control of the dopant distribution obtained already during the shaping process, without further machining or bonding. The waveguides are composed of a laser active Yb:YAG layer obtained by tape casting with a thickness between 100 and 250 ?m placed between dopant-free YAG cladding obtained by oxide powder mixing. The refractive index of Yb:YAG is higher than YAG thus realizing a multimode waveguide. Two types of geometries were tested: 1. simple planar waveguide with a sandwich structure (confinement in one direction); 2. waveguide with a rectangular cross section (confinement in two directions). The waveguides were tested for laser emission in a cavity end pumped by a fiber coupled diode laser, under quasi-CW pumping conditions (rectangular pump pulses with 10 ms duration, 10 Hz), delivering up to 60W at 936 nm. The planar waveguide has shown a maximum output power of 14.4 W (slope efficiency 39.1%, optical efficiency 27.4%) whereas the 2D waveguide had a maximum output power of 11.6 W (slope efficiency 38.4%, optical efficiency 22.4%). Lasing wavelength was 1030 nm. The authors gratefully acknowledge the support from the Italian Ministry of Defence under PNRM, Contract No. 8731 of 04/12/2019 (CeMiLAP2).

We report on the spectroscopic and laser emission properties of 10 at% Yb:Y3ScxAl5-xO12 (Yb:YSAG) ceramic varying the amount of Sc (x) ranging from x = 0.25 to x = 1.5. The samples were fabricated by a solid state reaction method followed by vacuum sintering and annealing in air. The spectroscopic investigation has evidenced an increased broadening in both the absorption and the emission spectra for increasing Sc content, as well as an extension of lifetime at increased Sc content. Concerning the laser performance, the maximum slope efficiency, i.e. 76.6%, was obtained with the sample with x = 0.25 while the largest tuning range, i.e. 81 nm, with the sample having the highest concentration of Sc ions (x = 1.5); a steady broadening in the tuning bandwidth for increasing Scandium content was measured.

In this paper we report on the preparation and laser performance of transparent 3aL% Yb:Sc2O3 ceramics by reactive sintering of commercially available powders under vacuum followed by hot isostatic pressing (HIP). Combinations of different vacuum sintering temperatures (1650 degrees C and 1750 degrees C) and different HIP treatments (1700 degrees C and 1800 degrees C at 200 MPa) were tested in order to understand how these steps influence the microstructure and thus the optical and lasing properties of the ceramic samples. All the samples showed a good optical quality. The microstructure analysis and the laser tests showed that the vacuum pre-sintering temperature is the key factor determining the quality of the samples and the laser performances. The best values of slope efficiency i.e. eta(L) = 50 % and output power i.e. P-out = 6.62 W were obtained for the sample pre-sintered under vacuum at 1650 degrees C and hot isostatically pressed at 1800 degrees C.

An excursus on the achievements in transparent ceramics doped with Yb and Tm for diode-pumped solid-state lasers is reported. Future perspectives of ceramics for visible lasers will be discussed.

In this article, 5 at.% Yb:Lu2O3 transparent ceramics were fabricated by vacuum sintering combined with hot isostatic pressing (HIP) posttreatment using co-precipitated nano-powders. The influence of precipitant molar ratio, ammonium hydrogen carbonate, to metal ions (AHC/M3+, R value) on the properties of Yb:Lu2O3 precursors and calcined powders was investigated systematically. It was found that the powders with different R value calcined at 1100 degrees C for 4 hours were pure cubic Lu2O3 but the morphologies of precursors and powders behaved differently. The opaque samples pre-sintered at 1500 degrees C for 2 hours grew into transparent ceramics after HIP posttreatment at 1750 degrees C for 1 hour. The final ceramic with R = 4.8 showed the best optical quality with the in-line transmittance of 79.7% at 1100 nm. The quasi-CW laser operation was performed at 1034 nm and 1080 nm with a maximum output power up to 8.15 W as well as a corresponding slope efficiency of 58.4%.

Thulium doped mixed sesquioxides are well suited for the generation of ultra-short laser pulses in the 2-μm spectral range and for the extension of the laser tuning interval due to formation of solid solutions exhibiting a non-uniform distribution of the crystal field in the dopant occupation sites [1] , [2] . This effect inhomogeneously broadens the absorption and the emission spectra of the lasing ions with respect to the "pure" compositions.

At present, searching for new efficient red light-emitting phosphors remains extremely relevant for obtaining warm white light from phosphor-converted white LEDs (pc-WLEDs). Appropriate phosphors should have significant absorption in the blue spectral range and emit in the red range of 620 ÷ 650 nm. Mn 4+ -doped luminescent materials with narrow-band emission due to the Mn 4+ d-d electronic transition have been subjected to intensive studies in the last years as promising red-emitting phosphors efficiently excited with blue LEDs.

Flavohemoglobins have the particular capability of binding unsaturated and cyclopropanated fatty acids as free acids or phospholipids. Fatty acid binding to the ferric heme results in a weak but direct bonding interaction. Ferrous and ferric protein, in presence or absence of a bound lipid molecule, have been characterized by transient absorption spectroscopy. Measurements have been also carried out both on the ferrous deoxygenated and on the CO bound protein to investigate possible long-range interaction between the lipid acyl chain moiety and the ferrous heme. After excitation of the deoxygenated derivatives the relaxation process reveals a slow dynamics (350 ps) in lipid-bound protein but is not observed in the lipid-free protein. The latter feature and the presence of an extra contribution in the absorption spectrum, indicates that the interaction of iron heme with the acyl chain moiety occurs only in the excited electronic state and not in the ground electronic state. Data analysis highlights the formation of a charge-transfer complex in which the iron ion of the lipid-bound protein in the expanded electronic excited state, possibly represented by a high spin Fe III intermediate, is able to bind to the sixth coordination ligand placed at a distance of at 3.5 A from the iron. A very small nanosecond geminate rebinding is observed for CO adduct in lipid-free but not in the lipid-bound protein. The presence of the lipid thus appears to inhibit the mobility of CO in the heme pocket.

Samples of magnesium aluminum spinel ceramics doped with manganese ions were prepared by a high-temperature solid-state reaction method, their potential as red-emitting phosphors was analyzed using a time-resolved luminescence spectroscopy technique, from room temperature to 10 K. It was found that in the red spectral range, the luminescence spectra of manganese ions in the MgAl2O4 spinel showed a narrow band peaking at 651 nm due to the emission of Mn4+ and a broader emission band in the region of 675 &divide, 720 nm, the ratio of intensities for these bands depends on the synthesis conditions. By applying a special multi-step annealing procedure, the MgAl2O4:Mn4+ phosphor containing only tetravalent manganese ions, Mn4+, was synthesized. Broad-band far-red emission observed from MgAl2O4:Mn and Mg1.25Al1.75O3.75F0.25:Mn phosphors, prepared by a conventional method of a solid-state reaction, was interpreted as coming from Mn3+ ions.

European physical journal special topics 229(24), 3675 - 4284 (2020). doi:10.1140/epjst/e2020-000127-8, This report presents the conceptual design of a new European research infrastructure EuPRAXIA. The concept has been established over the last four years in a unique collaboration of 41 laboratories within a Horizon 2020 design study funded by the European Union. EuPRAXIA is the first European project that develops a dedicated particle accelerator research infrastructure based on novel plasma acceleration concepts and laser technology. It focuses on the development of electron accelerators and underlying technologies, their user communities, and the exploitation of existing accelerator infrastructures in Europe. EuPRAXIA has involved, amongst others, the international laser community and industry to build links and bridges with accelerator science — through realising synergies, identifying disruptive ideas, innovating, and fostering knowledge exchange. The Eu-PRAXIA project aims at the construction of an innovative electron accelerator using laser- and electron-beam-driven plasma wakefield acceleration that offers a significant reduction in size and possible savings in cost over current state-of-the-art radiofrequency-based accelerators. The foreseen electron energy range of one to five gigaelectronvolts (GeV) and its performance goals will enable versatile applications in various domains, e.g. as a compact free-electron laser (FEL), compact sources for medical imaging and positron generation, table-top test beams for particle detectors, as well as deeply penetrating X-ray and gamma-ray sources for material testing. EuPRAXIA is designed to be the required stepping stone to possible future plasma-based facilities, such as linear colliders at the high-energy physics (HEP) energy frontier. Consistent with a high-confidence approach, the project includes measures to retire risk by establishing scaled technology demonstrators. This report includes preliminary models for project implementation, cost and schedule that would allow operation of the full Eu-PRAXIA facility within 8—10 years., Published by Springer, Heidelberg

The first highly efficient laser action was demonstrated in Yb-doped (Y,Sc) 2 O 3 transparent ceramics under a quasi-continuous wave diode end pumping at 929.4 nm. The ceramic samples were fabricated using solid-state vacuum sintering of mixed sesquioxide nanoparticles with various Y/Sc balances synthesized by laser ablation. For the (Yb 0.058 Sc 0.508 Y 0.434 ) 2 O 3 ceramic we measured a maximum output power of 5 W at 1086 nm while the highest slope efficiency was 61.3%.

Cold-adapted organisms have evolved proteins endowed with higher flexibility and lower stability in comparison to their thermophilic homologues, resulting in enhanced reaction rates at low temperatures. In this context, protein-bound water molecules were suggested to play a major role, and their weaker interactions at protein active sites have been associated with cold adaptation. In this work, we tested this hypothesis on truncated hemoglobins (a family of microbial heme-proteins of yet-unclear function) applying molecular dynamics simulations and ligand-rebinding kinetics on a protein from the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 in comparison with its thermophilic Thermobifida fusca homologue. The CO rebinding kinetics of the former highlight several geminate phases, with an unusually long-lived geminate intermediate. An articulated tunnel with at least two distinct docking sites was identified by analysis of molecular dynamics simulations and was suggested to be at the origin of the unusual geminate rebinding phase. Water molecules are present in the distal pocket, but their stabilization by TrpG8, TyrB10, and HisCD1 is much weaker than in thermophilic Thermobifida fusca truncated hemoglobin, resulting in a faster geminate rebinding. Our results support the hypothesis that weaker water-molecule interactions at the reaction site are associated with cold adaptation. Fil: Boubeta, Fernando Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Boechi, Leonardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Estrin, Dario Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Patrizi, Barbara. Università di Firenze. Lens European Laboratory For Non-linear Spectroscopy; Italia. Istituto Nazionale di Ottica; Italia Fil: Di Donato, Mariangela. Università di Firenze. Lens European Laboratory For Non-linear Spectroscopy; Italia. Istituto Nazionale di Ottica; Italia Fil: Iagatti, Alessandro. Università di Firenze. Lens European Laboratory For Non-linear Spectroscopy; Italia Fil: Giordano, Daniela. Consiglio Nazionale delle Ricerche; Italia. Stazione Zoologica Anton Dohrn; Italia Fil: Verde, Cinzia. Consiglio Nazionale delle Ricerche; Italia. Stazione Zoologica Anton Dohrn; Italia Fil: Bruno, Stefano. Università di Parma; Italia Fil: Abbruzzetti, Stefania. Università di Parma; Italia Fil: Viappiani, Cristiano. Università di Parma; Italia

This paper is devoted to summarizing and discussing the scientific progress achieved during the past decade in diode-pumped ytterbium-doped solid-state lasers. The output radiation centered on the 1- μ m region is of particular interest for the well-known applications of previously developed Nd3+ lasers. Several hosts have been studied and tested in recent years. Due to the enormous number of papers dealing with ytterbium, Yb 3+, doped hosts, we will limit our report here to materials based on transparent polycrystalline sesquioxide laser ceramics, such as Lu2O3, Sc2O3, and Y2O3 . The reason is basically due to the wider emission band of ytterbium-doped sesquioxides as compared with more commonly used hosts such as YAG. The higher thermal conductivity with respect to hosts such as CaF2 makes them very interesting for applications requiring both good thermal conductivity and a wide fluorescence emission band, as well as for short pulse generation at high average power levels. Furthermore, the replacement of trivalent Yb in sesquioxides does not require any charge compensation (as is the for instance case of the replacement of divalent Ca in CaF2), which makes their fabrication easier, in particular at high doping levels.

We report on the first laser action of a (Tm0.05Sc0.252Y0.698)2O3 ceramic sample, which was made by solid-state vacuum sintering of laser-ablated mixed sesquioxide nanoparticles. Pumped at 793 nm in quasi-CW mode, it delivers 1.24 W with a slope efficiency of 9.45% at 2076 nm. We have measured the absorption spectra at several temperatures, from 93 K to 293 K, calculating the absorption coefficients by Lambert-Beer formula. Moreover, emission cross sections were calculated by Fuchtbauer-Ladenburg starting from the fluorescence spectra measured at room temperature. Spectroscopic data where compared with those obtained by (Tm0.05Y0.95)2O3 fabricated with the same method. Finally, the ceramic tunability was explored finding a tuning range as broad as 181 nm (from 1927.5 nm to 2108.5 nm).

Comorbidity between borderline personality disorder (BPD) and alcohol use disorder (AUD) is high and relevant as alcohol consumption seems to worsen BPD symptomatology. One of the newest treatments for AUD, nalmefene, may be useful to improve BPD symptoms not only indirectly by reducing alcohol consumption but also directly by acting on the opioid system as this system has been related to specific BPD symptoms. This open-label study aimed at evaluating the efficacy of an 8-week nalmefene treatment in reducing alcohol consumption in individuals with BPD and comorbid AUD. A secondary objective was to assess its efficacy in improving general BPD symptomatology and specific behaviors (self injury and binge eating). Eighteen out of the 25 patients with BPD and comorbid AUD enrolled in the study completed all the assessment points. After 8 weeks, a significant reduction was observed in alcohol consumption, BPD global symptomatology, self-injurious behavior, and binge eating. No serious adverse effects were reported; however, five participants experienced mild side effects, resulting in withdrawal from the study in two cases. According to our results, nalmefene may be a safe and effective drug for treating patients with BPD and comorbid AUD. Controlled clinical trials are needed to support our findings. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.

Optical materials: X 8, 100065 (2020). doi:10.1016/j.omx.2020.100065, Published by Elsevier, Amsterdam

Yb3+-doped Lu2O3 nanoparticles produced by laser ablation were used to fabricate transparent ceramics by a combination of pressureless sintering in vacuum (PS) followed by a hot isostatic pressing (HIPing). The samples were subjected to various PS and HIPing conditions and the microstructure evolution and its correlation with the transmittance were investigated. Relative densities of over 97% were achieved after PS at the temperatures of 1250–1700 °C. Rapid grain growth occurred within PS and HIPing temperatures above 1500 °C leading to formation of intragranular porosity which is deleterious for optical quality. Higher transmittance (81.7% at λ = 1080 nm) and ultrafine microstructure with an average grain size of 0.35 μm were obtained by PS at 1250 °C followed by HIPing at 1400 °C for 5 h under 207 MPa. Output power of 2.02 W with a slope efficiency of 46.5% was obtained under a quasi-continuous wave end pumping at 929.4 nm.

The FAMU experiment aims to measure for the first time the hyperfine splitting of the muonic hydrogen ground state. From this measurement the proton Zemach radius can be derived and this will shed light on the determination of the proton charge radius. In this paper, we describe the scientific goal, the method and the detailed preparatory work. This includes the outcome of preliminary measurements, subsequent refined simulations and the evaluation of the expected results. The experimental setup being built for the measurement of the hyperfine splitting to be performed at the RAL laboratory muon facility is also described.

Rapporto tecnico finale sulle attività del progetto CeMiLAP "CERAMICHE MICROSTRUTTURATE TRASPARENTI PER APPLICAZIONI LASER DI ALTA POTENZA: SVILUPPO E VALIDAZIONE"

A lithography-based additive manufacturing technique was used for the first time to produce laser-emitting transparent 10 at.% Yb-doped yttrium aluminum garnet (Yb:YAG) ceramics from a mixture of oxide powders as starting materials. The ceramics were densified by vacuum sintering. Output power of more than 2.16 W and a slope efficiency of 17.6% were achieved under quasi-continuous-wave laser pumping.

The comprehensive characterization of Intramolecular Charge Transfer (ICT) stemming in push-pull molecules with a delocalized π-system of electrons is noteworthy for a bespoke design of organic materials, spanning widespread applications from photovoltaics to nanomedicine imaging devices. Photo-induced ICT is characterized by structural reorganizations, which allows the molecule to adapt to the new electronic density distribution. Herein, we discuss recent photophysical advances combined with recent progresses in the computational chemistry of photoactive molecular ensembles. We focus the discussion on femtosecond Transient Absorption Spectroscopy (TAS) enabling us to follow the transition from a Locally Excited (LE) state to the ICT and to understand how the environment polarity influences radiative and non-radiative decay mechanisms. In many cases, the charge transfer transition is accompanied by structural rearrangements, such as the twisting or molecule planarization. The possibility of an accurate prediction of the charge-transfer occurring in complex molecules and molecular materials represents an enormous advantage in guiding new molecular and materials design. We briefly report on recent advances in ultrafast multidimensional spectroscopy, in particular, Two-Dimensional Electronic Spectroscopy (2DES), in unraveling the ICT nature of push-pull molecular systems. A theoretical description at the atomistic level of photo-induced molecular transitions can predict with reasonable accuracy the properties of photoactive molecules. In this framework, the review includes a discussion on the advances from simulation and modeling, which have provided, over the years, significant information on photoexcitation, emission, charge-transport, and decay pathways. Density Functional Theory (DFT) coupled with the Time-Dependent (TD) framework can describe electronic properties and dynamics for a limited system size. More recently, Machine Learning (ML) or deep learning approaches, as well as free-energy simulations containing excited state potentials, can speed up the calculations with transferable accuracy to more complex molecules with extended system size. A perspective on combining ultrafast spectroscopy with molecular simulations is foreseen for optimizing the design of photoactive compounds with tunable properties.

The Yb:Lu2O3 precursor made up of spherical particles was synthesized through the co-precipitation method in the water/ethanol solvent. The 5 at% Yb:Lu2O3 powder is in the cubic phase after calcination at 1100 °C for 4 h. The powder also consists of spherical nanoparticles with the average particle and grain sizes of 96 and 49 nm, respectively. The average grain size of the pre-sintered ceramic sample is 526 nm and that of the sample by hot isostatic pressing grows to 612 nm. The 1.0 mm-thick sample has an in-line transmittance of 81.6% (theoretical value of 82.2%) at 1100 nm. The largest absorption cross-section at 976 nm is 0.96×10−20 cm2 with the emission cross-section at 1033 nm of 0.92×10−20 cm2 and the gain cross sections are calculated with the smallest population inversion parameter β of 0.059. The highest slope efficiency of 68.7% with the optical efficiency of 65.1% is obtained at 1033.3 nm in quasi-continuous wave (QCW) pumping. In the case of continuous wave (CW) pumping, the highest slope efficiency is 61.0% with the optical efficiency of 54.1%. The obtained laser performance indicates that Yb:Lu2O3 ceramics have excellent resistance to thermal load stresses, which shows great potential in high-power solid-state laser applications.

Transparent Yb:Y3ScAl4O12 (Yb:YSAG) ceramics with different ytterbium doping concentrations such as 5, 10, 15, 20 at.% have been successfully fabricated by solid-state reactive sintering. All the obtained ceramics are in dense and homogeneous structure after sintering at 1820 degrees C for 30 hours and with a posttreatment by hot isostatic pressing at 1750 degrees C for 3 hours with 200 MPa pressure. We systematically analyzed the influence of Yb3+ doping concentration on the microstructure and optical properties of the ceramics. The 10 at.% Yb:Y3ScAl4O12 ceramics with a thickness of 3.2 mm show the best transparency as high as 80.9% at 1100 nm. The laser emission of the 10 at.% Yb:YSAG ceramics was tested, resulting in a maximum slope efficiency of 67.6% and a maximum output power of 11.3 W under quasi-continuous wave pump conditions. The tuning range spanned from 990 to 1071 nm.

Figure 20.1 was not correct in the published article. The original article has been corrected. The published apologizes for the inconvenience.

Rapporto tecnico della Fase 3 (ultima) del progetto CERAMICHE MICROSTRUTTURATE TRASPARENTI PER APPLICAZIONI LASER DI ALTA POTENZA: SVILUPPO E VALIDAZIONE "CeMiLAP" - FASE 3: Ottimizzazione del processo produttivo per la realizzazione di un dimostratore con diametro fino a 50 mm. Test del dimostratore in esercizio.

In the last years, there has been a huge improvement in Electro-Optical (EO) systems effectiveness, due to the availability of large staring arrays detectors with higher performance, as well as strong processing capability. So both in homeland surveillance and for military situational awareness, the use of EO systems, operating from Visible to Infrared, has dramatically grown. Operations in Degraded Visual Environment (DVE) are frequent during military actions, due to many factors: either natural (poor light, fog, glare etc.) or intentionally produced (smoke, dust etc.). In these conditions the performance of EO sensors is degraded and therefore their effectiveness for Detection, Recognition and Identification (DRI) and Navigation capability. In general, the situational awareness is strongly affected as well as the safety of personnel. Proper techniques are needed to restore (at least partially) the imaging capabilities of EO sensors in DVEs. The project SPIDVE (Study on EO Sensors Performance Improvement in Degraded Visual Environment), promoted by the European Defense Agency (EDA), is focused on the analysis of the impact on EO sensors performance by the adverse visual conditions. It starts from the analysis of the status of the art in terms of technology, processing, measurements and modeling methodologies, based on the existing scientific literature, to carry out an assessment of the most promising technologies for image enhancement and restoration in different DVEs. Particular care is devoted to the discussion with the final users (the military personnel) to identify the cases of higher interest for their operations. On this basis the possible candidate methodologies shall be analyzed more deeply, evaluating their performance with the aim of selecting the most promising one. At the end, a possible roadmap for new initiatives to exploit and develop the findings shall be defined.

The purpose of the European project EuPRAXIA is to realize a novel plasma accelerator user facility. The laser driven approach sets requirements for a very high performance level for the laser system: pulse peak power in the petawatt range, pulse repetition rate of several tens of Hz, very high beam quality and overall stability of the system parameters, along with 24/7 operation availability for experiments. Only a few years ago these performances were considered unrealistic, but recent advances in laser technologies, in particular in the chirped pulse amplification (CPA) of ultrashort pulses and in high energy, high repetition rate pump lasers have changed this scenario. This paper discusses the conceptual design and the overall architecture of a laser system operating as the driver of a plasma acceleration facility for different applications. The laser consists of a multi-stage amplification chain based CPA Ti:Sapphire, using frequency doubled, diode laser pumped Nd or Yb solid state lasers as pump sources. Specific aspects related to the cooling strategy of the main amplifiers, the operation of pulse compressors at high average power, and the beam pointing diagnostics are addressed in detail.

We report an in-depth investigation (fabrication, microstructure and spectroscopy) of Yb3+-doped mixed sesquioxide transparent ceramics (LuxY1−x)2O3 with x = 0, 0.113 and 0.232. The ceramics were fabricated by vacuum sintering of nano-sized particles synthesized by CO2 laser co-evaporation of the corresponding solid targets with different Y/Lu balance. The effect of Lu3+ concentration on crystal structure and phase evolution of the nanopowders and microstructure, optical and spectroscopic properties of the sintered ceramics was investigated. The micro-Raman measurements with high spatial resolution revealed a homogeneous distribution of both yttrium and lutetium in the mixed composition. The optical transmission of 1.4 mm-thick ceramics was over 80% in the wavelength range of 500–1100 nm. Partial substitution of Y3+ cations for Lu3+ cations determines a small shift toward longer wavelengths and broadening of the Yb3+ main emission peaks at about 1030 and 1076 nm. This is the first extensive characterization of the spectroscopic properties of Yb:(Y,Lu)2O3 compositional family in ceramic hosts.

25th International Conference on the Application of Accelerators in Research and Industry, CAARI 2018, Texas, USA, 12 Aug 2018 - 17 Aug 2018; AIP conference proceedings 2160(1), 040012-1 - 040012-9 (2019). doi:https://doi.org/10.1063/1.5127692, Plasma accelerators present one of the most suitable candidates for the development of more compact particle acceleration technologies, yet they still lag behind radiofrequency (RF)-based devices when it comes to beam quality, control, stability and power efficiency. The Horizon 2020-funded project EuPRAXIA (“European Plasma Research Accelerator with eXcellence In Applications”) aims to overcome the first three of these hurdles by developing a conceptual design for a first international user facility based on plasma acceleration. In this paper we report on the main features, simulation studies and potential applications of this future research infrastructure., Published by AIP Publishing, Melville, NY

We report a combined approach of stationary and time-resolved fluorescence measurements and ultraviolet-visible (UV-vis) transient absorption spectroscopy (TAS) along with ab initio calculations, which provide an overall picture of the dynamics occurring after excitation in a push-pull molecule, namely, 4,7-bis (4,5-dibutylbenzo[1,2-b:4,3-b?]bisthiophene[1,2-b:4,3-b?]bisthiophen-2-yl)-2,1,3-benzothiadiazole. The analysis of the emission spectra in solvents of different polarities reveals the presence of three conformers whose structures differ in the orientation of the 4,5-dibutylbenzo-bisthiophene groups and in their planarity with respect to the benzothiadiazole acceptor group. The Kawski method allows us to estimate the ground- and first-excited state dipole moments (? g and ? e ) for the three conformers. We find values of ? e similar for the three conformers and higher than the relative ? g values as can be expected from a push-pull molecule undergoing a light-induced charge-transfer (CT) transition. UV-vis TAS in different solvents highlights the instantaneous (within our instrumental resolution) formation of a locally excited S 1 state (accompanied by a big change in the dipole moment with respect to S 0 ), which undergoes a rapid intramolecular CT (ICT) assisted by molecule planarization [planar ICT (PICT)]. The strong dipole-dipole interactions with the polarized solvent molecules stabilize the S 1 CT state that decays principally through fluorescence emission. Both PICT and solvation dynamics are responsible for the big Stokes' shift characterizing the molecule, particularly in polar solvents. The fluorescence lifetimes are substantially longer in polar solvents, and also fluorescence quantum yields are higher in polar solvents. We conclude that the radiative relaxation time increases when molecular planarization of the S 1 emissive state takes place, and this condition is favored in polar solvents where local dipole-dipole interactions support the structural stabilization of the CT emissive state. In the poly(methyl methacrylate) matrix, the structural and solvation dynamics are strongly inhibited, leading to reduction of nonradiative processes and to shortening of the fluorescence relaxation time

Inhaled Loxapine (IL) has demonstrated efficacy in the treatment of agitation in schizophrenic and bipolar patients, although data in patients with Personality Disorder (PD) are scarce. To evaluate the effectiveness and safety of IL in the treatment of agitation in PD, data from 41 patients who presented at our unit with acute agitation and were treated with 9.1 mg of IL were collected retrospectively. The results showed that IL significantly decreased agitation within 10 minutes and its effect was greater at 20 minutes (Positive and Negative Syndrome Scale-excited component: from 22.78 ± 4.39 at baseline to 11.14 ± 4.17 at 20 minutes; p 0.001; Agitation and Calmness Evaluation Scale: from 1.80 ± 0.49 at baseline to 4.53 ± 1.05 at 20 minutes; p 0.01) without any severe adverse reactions registered. IL led to fast, safe and well-tolerated control of agitation in patients with PD.

One of the challenges for achieving efficient exciton transport in solar energy conversion systems is precise structural control of the light-harvesting building blocks. Here, we create a tunable material consisting of a connected chromophore network on an ordered biological virus template. Using genetic engineering, we establish a link between the inter-chromophoric distances and emerging transport properties. The combination of spectroscopy measurements and dynamic modelling enables us to elucidate quantum coherent and classical incoherent energy transport at room temperature. Through genetic modifications, we obtain a significant enhancement of exciton diffusion length of about 68% in an intermediate quantum-classical regime.

We report the fabrication procedure, the spectroscopic characterization and the laser performance of a 5 at.% Yb doped Sc2O3 ceramic sample fabricated by co-precipitation and vacuum sintering method. The characteristics of the precursor as well as the calcined powders are analyzed at each step by means of Brunauer- Emmett-Teller (BET), XRD, and SEM. Concerning the laser performance, quasi-CW laser oscillation is obtained at 1046.6 nm with a maximum output power of 2.44 W while the slope efficiency was 34.9%. Finally, the tunability measurement of this ceramic has revealed a very broad tuning range, i.e. 56 nm

We report a comprehensive characterization of a 10 at.% Yb3+-doped YSAG (Yb:Y3ScxAl(5−x)O12, x = 1.5) ceramic, including microstructural, spectroscopic and laser properties. Moreover, we illustrate and discuss the fabrication technique. Yb3+ in YSAG features a broader absorption and emission band than in traditional YAG, which is advantageous for laser applications (i.e., tunable laser sources, ultrafast pulse generation). Pumping in a quasi continuous wave regime at 936 nm, the ceramic has shown good laser performance as the maximum output power was 6.3 W with a corresponding slope efficiency (ηs) of 67.8%. In continuous wave regime instead, the maximum output power was 5 W with ηs = 52.7%. The laser emission wavelengths in free running were λL = 1051 nm and λL = 1031 nm, depending on the output coupler transmission. Finally, by a tunable cavity we obtained laser emission spanning from 991.5 to 1073 nm, i.e., 81.5 nm, which is the broadest tuning range ever reported for this material, to the best of our knowledge.