Terahertz Photoconductivity Spectra of Electrodeposited Thin Bi Films

Ignas Nevinskas, Zenius Mockus, Remigijus Juškėnas, Ričardas Norkus, Algirdas Selskis, Eugenijus Norkus, Arūnas Krotkus
2021 Materials  
Electron dynamics in the polycrystalline bismuth films were investigated by measuring emitted terahertz (THz) radiation pulses after their photoexcitation by tunable wavelength femtosecond duration optical pulses. Bi films were grown on metallic Au, Pt, and Ag substrates by the electrodeposition method with the Triton X-100 electrolyte additive, which allowed us to obtain more uniform films with consistent grain sizes on any substrate. It was shown that THz pulses are generated due to the
more » ... l separation of photoexcited electrons and holes diffusing from the illuminated surface at different rates. The THz photoconductivity spectra analysis has led to a conclusion that the thermalization of more mobile carriers (electrons) is dominated by the carrier–carrier scattering rather than by their interaction with the lattice.
doi:10.3390/ma14123150 fatcat:ncdql2xz3bhvja6mq2vtst7cwy