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Undoped Electron-Hole Bilayers in a GaAs/AlGaAs Double Quantum Well

J. A. Seamons·D. R. Tibbetts·J. L. Reno·M. P. Lilly
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Abstract

We present the fabrication details of completely undoped electron-hole bilayer devices in a GaAs/AlGaAs double quantum well heterostructure with a 30 nm barrier. These devices have independently tunable densities of the two-dimensional electron gas and two-dimensional hole gas. We report four-terminal transport measurements of the independently contacted electron and hole layers with balanced densities from $1.2 \times 10^{11}$cm$^{-2}$ down to $4 \times 10^{10}$ cm$^{-2}$ at $T = 300 mK$. The mobilities can exceed $1 \times 10^{6}$ cm$^{2}$ V$^{-1}$ s$^{-1}$ for electrons and $4 \times 10^{5}$ cm$^{2}$ V$^{-1}$ s$^{-1}$ for holes.

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J. A. Seamons, D. R. Tibbetts, J. L. Reno, M. P. Lilly. 2006-11-08. Undoped Electron-Hole Bilayers in a GaAs/AlGaAs Double Quantum Well. https://doi.org/10.1063/1.2437664

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