Magnetotransport properties of a polarization-doped three-dimensional electron slab

Abstract

We present evidence of strong Shubnikov-de-Haas magnetoresistance oscillations in a polarization-doped degenerate three-dimensional electron slab in an Al${}_x$Ga${}_{1-x}$N semiconductor system. The degenerate free carriers are generated by a novel technique by grading a polar alloy semiconductor with spatially changing polarization. Analysis of the magnetotransport data enables us to extract an effective mass of $m^{\star }=0.19m_0$ and a quantum scattering time of $\ddot{I}{„}_q=0.3ps$. Analysis of scattering processes helps us extract an alloy scattering parameter for the Al${}_x$Ga${}_{1-x}$N material system to be $V_0=1.8eV$.