Interaction of electrons with the confined LO phonons of a free-standing GaAs quantum wire

A continuum model is employed to describe the allowed longitudinal-optical phonons of a cylindrical free-standing GaAs wire. The electron-phonon interaction Hamiltonian is then obtained and used to calculate intrasubband transitions in the extreme quantum limit. The scattering rate is predicted to be markedly reduced compared with the bulk value, and compared with the value expected when the wire is not free standing. This result is due to the lack of LO interface modes in the free-standing situation.