Lifetime Of Anharmonic Decay Of Optical Phonons In Confined GaAs Structure

The expression for the lifetime of optical phonons in bulk material has been well researched; however, there aren’t enough estimations for the theoretical lifetime of optical phonons in confined structures. In this paper, the expression for lifetime of a confined optical phonon decaying in to two acoustical phonons in GaAs double heterointerface structures was derived. Using the expression for the displacement of the optical and acoustic phonons in three phonon decay process, the Hamiltonian of the anharmonic decay is calculated. From the Fermi golden rule, the rate of transition and theoretical lifetime of phonon was calculated.