Abstract
? 2022 Elsevier B.V.The structure, transport properties, and ΔR/R ultrafast spectra of Bi2TexSe3-x crystals are studied in this work. The lattice parameter c and saturation temperature of resistance increase with increasing Te concentration. There are two electron-phonon coupling processes in Bi2TexSe3-x crystals corresponding to the interactions between two topological surface states and phonons. The electron-phonon coupling of one surface state is dominant at low temperatures (T ≤ 40 K), and the coupling of the second surface state and phonon is significant. With increasing temperature, electron-phonon coupling in bulk Bi2TexSe3?x is enhanced, which weakens electron-phonon coupling of its surface states. A small amount of Te has little effect on the electron-phonon coupling for Bi2Se3 crystals.
NSTL
Elsevier