arXiv subjects

Robert Tomala

Publications and source records attributed to Robert Tomala.

2 recordsLinked to original sources

arXiv2025

Toward more performant eye safe lasers: effect of increasing sensitizer amount in Yb3+,Er3+:YAG transparent ceramic on its spectral characteristics

Developing efficient Er3+,Yb3+:YAG eye-safe lasers is a priority of modern laser technology. This paper focuses on the influence of the concentration of Yb3+ ions on the spectroscopic properties of Er3+,Yb3+:YAG transparent ceramics. Four samples with different concentrations of Yb3+ ions were prepared by solid-state reaction sintering. The study revealed the influence of Yb3+ ions on the microstructure and the sintering process. A high concentration of Yb3+ ions leads to the formation of Y3+-rich impurity phases and causes segregation of Er3+ and Yb3+ and Si4+ into these phases. The influence of Yb3+ ions on the shape of emission spectra and the lifetimes of both Er3+ and Yb3+ ions was shown. Changes in the spectroscopic properties were ascribed to increase in neat transfer between Yb3+ and Er3+ ions. IQE of Er3+ and Yb3+ luminescence were calculated, and optimal Er3+/Yb3+ ions ratio were proposed

cond-mat.mtrl-sci↗

arXiv2025

Above and beyond the laser induced anti Stokes broadband white light emission in rare earth manganese perovskites

Herein, an experimental and theoretical analysis of broadband laser-induced white light emission (LIWE) in lead-free perovskite under near-infrared excitation is reported. LIWE is a tunable emission influenced by excitation wavelength, power density, pressure, and temperature. The radiance profile presented in this work closely resembles the solar spectral distribution, suggesting potential for solid-state lighting and photovoltaic applications. Based on theoretical modelling, along with photophysical and photoconductivity characterisations, a mathematical description of the LIWE generation is presented. This model describes LIWE as a dynamical process that explains the supralinear dependence of the integrated emission intensity on laser power density, pressure, photophysical kinetics, and photocurrent associated with the emission phenomena under excitation at high laser power densities.

physics.optics↗