Terahertz Photoconductivity Spectra of Electrodeposited Thin Bi Films

Materials

Zenius Mockus¹  Remigijus Juškėnas¹  Ričardas Norkus¹  Eugenijus Norkus¹  Ignas Nevinskas¹  Arūnas Krotkus¹  Algirdas Selskis¹ 

[1] Center for Physical Sciences and Technology, Saulėtekio al. 3, LT-10257 Vilnius, Lithuania;

关键词: bismuth film;    electrodeposition;    terahertz emission;    terahertz photoconductivity spectra;    femtosecond laser;   

DOI  :  10.3390/ma14123150

来源: DOAJ

【 摘 要 】

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 spatial 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.

【 授权许可】

Unknown