Coherent lattice dynamics in topological insulator Bi2 Te3 probed with time-resolved optical second-harmonic generation

TY - JOUR

T1 - Coherent lattice dynamics in topological insulator Bi2 Te3 probed with time-resolved optical second-harmonic generation

AU - Bykov, Anton Y.

AU - Murzina, Tatiana V.

AU - Olivier, Nicolas

AU - Wurtz, Gregory A.

AU - Zayats, Anatoly V.

PY - 2015/8/28

Y1 - 2015/8/28

N2 - The dynamics of phonon modes in thin flakes of topological insulator Bi2Te3 has been studied using transient optical second-harmonic spectroscopy. Using the surface sensitivity of second-harmonic generation, the excitation and dynamics of a family of optical phonon modes are observed with a response dependent on the excitation polarization. Three coherent phonon modes, inaccessible in previous linear time-resolved optical measurements, were detected in the nonlinear dynamic response. A symmetry-allowed surface optical phonon mode in Bi2Te3 has been identified using surface and symmetry selectivity of the second-order up-conversion process. Possible second-harmonic generation mechanisms in Bi2Te3 as well as the enhanced sensitivity of the nonlinear processes for the phonon mode detection in topological insulators are discussed.

AB - The dynamics of phonon modes in thin flakes of topological insulator Bi2Te3 has been studied using transient optical second-harmonic spectroscopy. Using the surface sensitivity of second-harmonic generation, the excitation and dynamics of a family of optical phonon modes are observed with a response dependent on the excitation polarization. Three coherent phonon modes, inaccessible in previous linear time-resolved optical measurements, were detected in the nonlinear dynamic response. A symmetry-allowed surface optical phonon mode in Bi2Te3 has been identified using surface and symmetry selectivity of the second-order up-conversion process. Possible second-harmonic generation mechanisms in Bi2Te3 as well as the enhanced sensitivity of the nonlinear processes for the phonon mode detection in topological insulators are discussed.

UR - http://www.scopus.com/inward/record.url?scp=84941087514&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.92.064305

DO - 10.1103/PhysRevB.92.064305

M3 - Article

AN - SCOPUS:84941087514

SN - 1098-0121

VL - 92

JO - Physical Review B (Condensed Matter and Materials Physics)

JF - Physical Review B (Condensed Matter and Materials Physics)

IS - 6

M1 - 064305

ER -