Anomalous LO Phonon Lifetime in AlAs

M. Canonico; C. Poweleit; J. Menéndez; A. Debernardi; S. R. Johnson; Y.-H. Zhang

doi:10.1103/PhysRevLett.88.215502

Anomalous LO Phonon Lifetime in AlAs

M. Canonico, C. Poweleit, J. Menéndez, A. Debernardi, S. R. Johnson, and Y.-H. Zhang

Phys. Rev. Lett. 88, 215502 – Published 14 May 2002

Abstract

The temperature dependence of the frequencies and linewidths of the Raman-active longitudinal optical (LO) phonons in GaAs and AlAs have been measured. The low-temperature lifetime of the LO phonon in AlAs is found to be 9.7 ps, very close to the corresponding GaAs value of 9.5 ps. This contradicts early theoretical predictions. The agreement between theory and experiment can be restored when the accidental degeneracy between the AlAs LO phonon frequency and a feature in the two-phonon density of states is taken into account.

Received 20 November 2001

DOI:https://doi.org/10.1103/PhysRevLett.88.215502

Authors & Affiliations

M. Canonico, C. Poweleit, and J. Menéndez

Department of Physics and Astronomy, Arizona State University, Box 871504, Tempe, Arizona 85287-1504

A. Debernardi

Istituto Nazionale per la Fisica della Materia (INFM), Unitá di ricerca de Trieste Universitá e SISSA, Dipartimento Fisica Teorica, Strada Costiera 11, 34014 Trieste, Italy

S. R. Johnson and Y.-H. Zhang