We introduce an approach for the temperature stabilization of nonlinear-optic crystals during laser frequency conversion processes. This approach is based on the stabilization of the piezoelectric resonance (PR) frequency of the crystal, so that the crystal itself becomes a temperature sensor. Application of an electronic oscillator provides a remarkably handy way to determine the PR frequency.
View Article and Find Full Text PDFWe have introduced an approach for low optical absorption coefficient measurement of piezoelectric materials based on the piezoelectric resonance laser calorimetry (PRLC) method. An RF oscillator circuit provides a convenient way to track the piezoelectric resonance frequency during laser irradiation. In this work, the optical absorption coefficient of lithium triborate crystal under high-power IR laser irradiation was measured using the oscillator circuit and the conventional PRLC technique.
View Article and Find Full Text PDFWe have established earlier that 835-nm infrared laser irradiation results in a dose-dependent growth inhibition of human mesenchymal stem and melanoma cells and is able to induce cell death. In this work we have demonstrated that hydrogen sulfide donor NaHS is able to protect both cell types from the negative action of laser irradiation and the magnitude of protection depends on NaHS concentration. The mechanism of cell protection by NaHS is primarily attributable to its effects on intracellular processes occurring after irradiation, since the protective effect does not depend on whether NaHS is added before or after irradiation.
View Article and Find Full Text PDFContinuous low-intensity laser irradiation (LILI) affects the state of cells in culture, including their proliferation rate. Data collected with various cell models vary significantly, but most studies have reported positive effects of LILI on cell proliferation. The effects of continuous infrared LILI (835 nm) was studied using three independent different melanoma cell lines.
View Article and Find Full Text PDFHeavily Er-doped fibers (EDFs) based on P(2)O(5)-Al(2)O(3)-SiO(2) (PAS) ternary glass have been studied. A unique feature of this glass is the formation of a AlPO(4) join having a structure similar to that of SiO(2) glass and a refractive index below it. It is found that the Er(3+) absorption and emission spectra in the PAS EDFs are defined by the dopant (Al(2)O(3) or P(2)O(5)) present in excess and are close to those of the corresponding binary glass (Al(2)O(3)-SiO(2) or P(2)O(5)-SiO(2)).
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