Plasma Dynamics Characterization for Improvement of Resonantly Enhanced Harmonics Generation in Indium and Tin Laser-Produced Plasmas

R.A.G. is grateful to H. Kuroda for providing the access to the laser facility. As a Center of Excellence, the Institute of Solid State Physics at the University of Latvia received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement no. 739508, project CAMART².In this study, we characterize the properties of indium and tin laser-induced plasmas responsible for efficient high-order harmonics generation of the ultrashort pulses propagating through these media. The optimally formed plasma was determined using the analysis of the time-resolved variations in the spectral and morphological features of spreading indium and tin plasma components under different regimes of laser ablation. We report the measurements of plasma velocities under different regimes of ablation and correlate them with the optimal delay between the heating and probe laser pulses for the generation of harmonics with the highest yield. Electron temperatures and densities are determined using the integrated and time-resolved spectral measurements of plasmas. The resonance-enhanced harmonics are compared with other harmonics from the point of view of the modulation of plasma characteristics. The harmonics of 800 and 1200–2200 nm lasers and their second-harmonic fields were analyzed at optimal conditions of Sn and In plasma formation. The novelty of this work is the implementation of the diagnostics of the dynamics of plasma characteristics for the determination of the optimal plasma formation for harmonics generation. Such an approach allows for the demonstration of the maximal harmonic yield from the studied plasma and the definition of the various resonance-induced harmonic generation conditions. © 2022 by the authors.European Regional Development Fund (1.1.1.5/19/A/003); Institute of Solid-State Physics, University of Latvia has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase 2 under grant agreement No. 739508, project CAMART2

High-order harmonics generation in Cd and Pd laser-induced plasmas

R.A.G. is grateful to H. Kuroda for providing access to the laser facility. Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.We demonstrate the generation of high-order harmonics of laser pulses in palladium and cadmium plasmas. We adjusted the wavelength of driving pulses to investigate the resonance enhancement in different ranges of extreme ultraviolet region. The summation of incommensurate waves during the two-color pump of Pd and Cd plasmas allowed the generation of a broader range of harmonics. The theoretical aspects of the two-color pump of the laser-induced plasma are discussed. © 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement --//-- This is an open access article Rashid A. Ganeev, Vyacheslav V. Kim, Jelena Butikova, Aigars Atvars, Jurgis Grube, Anatolijs Sarakovskis, and Arnolds Ubelis, "High-order harmonics generation in Cd and Pd laser-induced plasmas," Opt. Express 31, 26626-26642 (2023), https://doi.org/10.1364/OE.493754 published under the CC BY 4.0 licence.European Regional Development Fund (1.1.1.5/19/A/003); World Bank Project (REP-04032022-206).Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2

Thickness-dependent properties of ultrathin bismuth and antimony chalcogenide films formed by physical vapor deposition and their application in thermoelectric generators

This work was supported by the European Regional Development Fund (ERDF) project No 1.1.1.1/16/A/257. J. A. acknowledges the ERDF project No. 1.1.1.2/1/16/037. Institute of Solid State Physics, University of Latvia, Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017 TeamingPhase2 under grant agreement No. 739508, project CAMART2 . The raw/processed data required to reproduce these findings cannot be shared at this time as the data also form a part of an ongoing study.In this work, a simple cost-effective physical vapor deposition method for obtaining high-quality Bi2Se3 and Sb2Te3 ultrathin films with thicknesses down to 5 nm on mica, fused quartz, and monolayer graphene substrates is reported. Physical vapor deposition of continuous Sb2Te3 ultrathin films with thicknesses 10 nm and below is demonstrated for the first time. Studies of thermoelectrical properties of synthesized Bi2Se3 ultrathin films deposited on mica indicated opening of a hybridization gap in Bi2Se3 ultrathin films with thicknesses below 6 nm. Both Bi2Se3 and Sb2Te3 ultrathin films showed the Seebeck coefficient and thermoelectrical power factors comparable with the parameters obtained for the high-quality thin films grown by the molecular beam epitaxy method. Performance of the best Bi2Se3 and Sb2Te3 ultrathin films is tested in the two-leg prototype of a thermoelectric generator.ERDF project No 1.1.1.1/16/A/257; ERDF project No. 1.1.1.2/1/16/037; Institute of Solid State Physics, University of Latvia, Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017 TeamingPhase2 under grant agreement No. 739508, project CAMART

Спектры возбуждения и фотолюминисценции твердых растворов на основе индата лантана со структурой перовскита, легированного ионами Pr3+, Nd3+, Cr3+

Excitation and photoluminescence spectra of La0,997Pr0,003InO3, La0,98Nd0,02InO3, La0,977Pr0,003Nd0,02InO3, La0,977Pr0,003Nd0,02In0,99Cr0,01O3, LaIn,099Cr0,01O3 solid solutions have been studied. It has been found that Cr+ ions incorporated into the In3++ sublattice of La0,977Pr0,003Nd0,02In0,99Cr0,01O3 solid solution can act as Nd3+ photoluminescence sensitizers under the excitation by visible light (λ = 445 nm).Исследованы спектры возбуждения и фотолюминесценции твердых растворов La0,997Pr0,003InO3, La0,98Nd0,02InO3, La0,977Pr0,003Nd0,02InO3, La0,977Pr0,003Nd0,02In0,99Cr0,01O3, LaIn0,99Cr0,01O3. Установлено, что ионы Cr3+, введенные в под-решетку ионов In3+ твердого раствора La0,977Pr0,003Nd0,02In0,99Cr0,01O3, являются сенсибилизаторами фотолюминесценции ионов Nd3+ при их возбуждении светом видимой области спектра (λ = 445 нм)

LASER-INDUCED PLASMA SPECTROSCOPY OF PLASMA FACING MATERIALS

Abstract Qualitative elemental analysis of ASDEX divertor plates' material was performed by laser-induced plasma spectroscopy. The spectra show a decrease in impurity signals and an increase in substrate signal during the layer-by-layer ablation. The selective detection of the plasma light is reasonable for obtaining emission spectra resembling those attained using time-gated detectors

A stability study of transparent conducting WO3/Cu/WO3 coatings with antimicrobial properties

This study was financially supported by ERDF project No. 1.1.1.1/21/A/050 “Large area deposition technologies of multifunctional antibacterial and antiviral nanocoatings”. The Institute of Solid State Physics, University of Latvia, as a Center of Excellence, has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART².WO3/Cu/WO3 coatings are transparent electrodes, but conductivity and transmittance have been observed to decrease with time. This paper reports the improved stability of WO3/Cu/WO3 coatings deposited by magnetron sputtering on glass and polyethylene terephthalate substrates. The stability issues due to Cu oxidation and migration can be addressed by adjusting the deposition parameters. Lowering the sputtering pressure results in denser WO3 films, confirmed by spectroscopic ellipsometry, and thus more stable coatings. The coatings retain their properties in an inert atmosphere, indicating that Cu oxidation is the main reason for the decrease in conductivity, rather than its migration observed by X-ray photoelectron spectroscopy. Optical property modeling is used to optimize the thickness of the three-layer coatings to obtain the highest figure-of-merit for a transparent electrode. A structure of glass/WO3 (70 nm)/Cu (10 nm)/WO3 (45 nm) gives a sheet resistance of 14 Ω/sq. and a light transmittance of 65% at 600 nm. In addition, the antimicrobial properties of these coatings are revealed. A decrease up to 105 of the gram-negative Escherichia coli and gram-positive Staphylococcus aureus bacterial colony formation units is found for several WO3/Cu/WO3-based coatings. In the case of the MS2 (Emesvirus zinderi) bacteriophage, a decrease in infectious particles for up to 104 plaque-forming units is obtained. The results indicate that more stable samples also had higher antimicrobial activity. --//-- This is an open access article M. Zubkins, V. Vibornijs, E. Strods, I. Aulika, A. Zajakina, A. Sarakovskis, K. Kundzins, K. Korotkaja, Z. Rudevica, E. Letko, J. Purans, A stability study of transparent conducting WO3/Cu/WO3 coatings with antimicrobial properties, Surfaces and Interfaces, Volume 41, 2023, 103259, ISSN 2468-0230, https://doi.org/10.1016/j.surfin.2023.103259 published under the CC BY licence.ERDF project No. 1.1.1.1/21/A/050. The Institute of Solid State Physics, University of Latvia, as a Center of Excellence, has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART²