Transport properties of the two-dimensional electron gas in AlP quantum wells at zero temperature

Abstract

Due to strain and confinement effects, the two-dimensional electron gas in AlP has a valley degeneracy ${g}_{v}=1$ for quantum well width $L<{L}_{c}=45.7\phantom{\rule{0.3em}{0ex}}\mathrm{\AA{}}$ and a valley degeneracy of ${g}_{v}=2$ for quantum well width $L>{L}_{c}$. We present theoretical results for transport properties of the electron gas for the two cases. We calculate the mobility of the two-dimensional electron gas at zero temperature for interface-roughness scattering and for impurity scattering. We discuss the transport scattering time, the single-particle relaxation time, and the magnetoresistance in a parallel magnetic field. Our calculations are important (i) for the design of AlP quantum well structures, (ii) to get insight into relevant microscopic parameters of different scattering mechanisms, and (iii) to obtain information about the electronic properties of the electron gas at low density where many-body effects and localization effects are important.