title: Coherent optical phonon generation in Bi3Ge4O12.
abstract: Time-domain spectroscopy of coherent optical phonons in bismuth germinate (Bi4Ge3O12) is presented. Utilizing both impulsive stimulated Raman scattering and time-domain terahertz spectroscopy, more than 12 unique vibrational states ranging in frequency from 2 to 11 THz are identified, each with coherent lifetimes ranging from 1 to 20 ps. These modes are highly sensitive to crystal orientation and demonstrate frequency shifts on picosecond timescales consistent with an anharmonic lattice potential.
authors.affiliation: Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.forename: Y
authors.initials: Y
authors.lastname: Gao
authors.forename: B C
authors.initials: BC
authors.lastname: Minch
authors.forename: M F
authors.initials: MF
authors.lastname: Decamp