0000000000370997
AUTHOR
Vj. Gerbreders
<title>Second harmonic generation in selenium thin films</title>
Results of second harmonic (SH) generation in amorphous and crystalline selenium films induced by titanium-sapphire femtosecond laser (wavelength λ - 800-1000 nm) are presented. It is found that the highest intensity of SH is provided by fundamental wave at wavelength 1000 nm and it reaches maximum in approximately 100 sec. The intensity of transmitted SH depends on film thickness while that of reflected does not.
Second harmonic generation in selenium-metal structures
The article examines the processes of second harmonic generation (SHG) when selenium-metal (Cu) film structures are illuminated by femtosecond radiation (180 fs, 80 MHz) at wavelength 800 – 1000 nm. Selenium-copper structures were obtained by successive thermal evaporation of selenium and copper onto the glass substrate in vacuum. Microanalysis of the film composition was performed to determine amount of copper in thin films. The as-evaporated selenium-copper structures were crystallised by annealing in inert atmosphere at temperature 85°C. Just evaporated as well as annealed thin films were explored. The experiment was performed by confocal microscope [1] where the femtosecond radiation fr…