Open AccessЗакономерности температурных изменений спектров отражения инфракрасного излучения кристалла Bi-=SUB=-0.8-=/SUB=-Sb-=SUB=-1.2-=/SUB=-Te-=SUB=-3-=/SUB=- в области возбуждения плазменнных колебаний свободных носителей заряда и межзонных переходов
Author(s) -
Н.П. Степанов,
А.А. Калашников
Publication year - 2021
Publication title -
optika i spektroskopiâ
Language(s) - English
Resource type - Journals
eISSN - 2782-6694
pISSN - 0030-4034
DOI - 10.21883/os.2021.05.50888.294-20
Subject(s) - valence band , plasmon , absorption edge , plasma , spectral line , redistribution (election) , band gap , dielectric , atomic physics , valence (chemistry) , chemistry , materials science , condensed matter physics , optoelectronics , physics , organic chemistry , quantum mechanics , astronomy , politics , political science , law
The regularities of the temperature behavior of the reflection spectra of the Bi0.8Sb1.2Te3 crystal obtained in the range of the plasma resonance of free charge carriers and the fundamental absorption edge allow us to trace the changes in the plasmon energy Ep and the optical band gap Eg opt. The observed decrease in Eg opt with increasing temperature corresponds to the existing ideas about the redistribution of holes between the nonequivalent extremes of the valence band in (Bi2-xSbx)Te3 (0<x<1) crystals. The dominance of this process in a certain temperature range contributes to the change in plasma frequencies. Keywords: reflection spectra, plasma oscillations, electron-plasmon interaction, dielectric functions.