Premium
Anomalous Behavior of the Elastic and Optical Properties in Bi 1.5 Sb 0.5 Te 1.8 Se 1.2 Topological Insulator Induced by Point Defects
Author(s) -
Zhevstovskikh Irina V.,
Ponosov Yuri. S.,
Titova Svetlana G.,
Averkiev Nikita S.,
Gudkov Vladimir V.,
Sarychev Maksim N.,
Kuznetsova Tatyana V.,
Kokh Konstantin A.,
Tereshchenko Oleg E.
Publication year - 2018
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.201800264
Subject(s) - materials science , condensed matter physics , trigonal crystal system , raman spectroscopy , topological insulator , excitation , elastic modulus , atmospheric temperature range , softening , attenuation , single crystal , optics , crystal structure , crystallography , physics , chemistry , composite material , quantum mechanics , meteorology
The experimental evidence of the defects influence on the optical and elastic properties of single crystal Bi 1.5 Sb 0.5 Te 1.8 Se 1.2 has been reported. The extra vibrational excitation is observed in the Raman spectrum near 125 cm −1 . Its line width has increased substantially with the increasing temperature, and its frequency shows a sharp softening in the temperature range of 200–250 K. In the same temperature range, a large peak in attenuation of longitudinal ultrasound wave propagating along the trigonal axis and the anomalous behavior of elastic modulus C 33 are found. These results indicate the presence of disorder in Bi 1.5 Sb 0.5 Te 1.8 Se 1.2 induced by the bulk defects. The antisite and interstitial defects on Bi/Sb and Te/Se(1) sublattices have been considered as the most probable ones.