Electron-Phonon Scattering in AlAs and Its Response to Hydrostatic Pressure

摘要

We perform first principles calculations to predict the electron-phonon (e-ph) scattering rates in AlAs and their dependence on phonon modes at energies close to the conduction band minima (CBM), as well as high into the conduction band. We then study the effect of hydrostatic pressure on the e-ph scattering in AlAs for pressures up to similar to 8.77 GPa. The effect of such pressures on the electronic structure and phonon dispersion is well documented. In AlAs, the bandgap becomes smaller, whereas the effect on phonon dispersion is to shift the optical phonon bands to higher frequencies and the acoustic branches to lower frequencies. In light of this, we explore the effect of hydrostatic pressure on the resulting scattering rates with increasing pressure along the high symmetry L - Gamma - X path. The results suggest that hydrostatic pressure does not significantly affect electron-phonon scattering rate.