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arXiv · cond-mat/0312638

Electron Scattering in AlGaN/GaN Structures

S. Syed·M. J. Manfra·Y. J. Wang·R. J. Molnar·H. L. Stormer
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Abstract

We present data on mobility lifetime, $τ_t$, quantum lifetime, $τ_q$, and cyclotron resonance lifetime, $τ_{CR}$, of a sequence of high-mobility two-dimensional electron gases in the AlGaN/GaN system, covering a density range of $\sim1-4.5\times10^{12}$cm$^{-2}$. We observe a large discrepancy between $τ_q$ and $τ_{CR}$ ($τ_q\simτ_{CR}$/6) and explain it as the result of density fluctuations of only a few percent. Therefore, only $τ_{CR}$ --and not $τ_q$ -- is a reliable measure of the time between electron scattering events in these specimens. The ratio $τ_t / τ_{CR}$ increases with increasing density in this series of samples, but scattering over this density range remains predominantly in the large-angle scattering regime.

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S. Syed, M. J. Manfra, Y. J. Wang, R. J. Molnar, H. L. Stormer. 2003-12-24. Electron Scattering in AlGaN/GaN Structures. https://doi.org/10.1063/1.1655704

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