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The terahertz phonon laser: a full quantum treatment

I. Camps·S. S. Makler·H. M. Pastawski·L. E. F. Foa Torres
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Abstract

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-AlGaAs 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_2) and transversal acoustic (TA) phonons. The last ones form an intense beam of coherent acoustic phonons. To study this effect, we start from a tight binding Hamiltonian that take into account the electron-phonon (e-ph) and phonon-phonon (ph-ph) interactions. We calculate the electronic current through the double barrier and we 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.

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I. Camps, S. S. Makler, H. M. Pastawski, L. E. F. Foa Torres. 2001-01-04. The terahertz phonon laser: a full quantum treatment. https://doi.org/10.1103/physrevb.64.125311

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