Coherent phonons in Bi2Se3 induced by a powerful THz pulse

Abstract

Using the electro-optic detection method we have detected coherent phonons of E1g1uE, 2g E , and 121g A symmetry generated in a crystalline film of Bi2Se3 by a powerful single-cycle THz pulse. Coherent excitation of Raman active modes is interpreted as a result of three-and fourphonon interactions in the anharmonic crystal lattice of Bi2Se3.