GaAs-AlxGa1ÀxAs double-barrier heterostructure phonon laser: A full quantum treatment

I. CAMPS; S. S. MAKLER; H. M. PASTAWSKI; L. E. F. FOA TORRES

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

The American Physical Society

Año: 2001 vol. 64 p. 125311 - 125311

0163-1829

GaAs-AlxGa1ÀxAs double-barrier heterostructure phonon laser: A full quantum treatmentI. Camps, S. S. Makler, H. M. Pastawski, and L. E. F. Foa TorresAbstract:The aim of this work is to describe the behavior of a device capable to generate high-frequency (~THz) acoustic phonons. This device consists in a GaAs-AlxGa12xAs double-barrier heterostructure that, when an external bias is applied, produces a high rate of longitudinal optical (LO) phonons. These LO phonons are confined and they decay by stimulated emission of a pair of secondary longitudinal optical (LO) and transversal acoustic phonons. The last ones form an intense beam of coherent acoustic phonons. To study this effect, we start from a tight-binding Hamiltonian that takes into account the electron-phonon and phonon-phonon interactions. We calculate the electronic current through the double barrier and obtain a set of five coupled kinetic equations that describes the electron and phonon populations. The results obtained here confirm the behavior of the terahertz phonon laser, estimated by rougher treatments @S.S. Makler et al., J. Phys.: Condens. Matter 10, 5905 ~1998!.# DOI: 10.1103/PhysRevB.64.125311 PACS number~s!: 73.23.2b, 73.40.Gk, 63.20.Kr