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arXiv · 0807.0106

Fabrication of closely spaced, independently contacted Electron-Hole bilayers in GaAs-AlGaAs heterostructures

J. A. Keogh·K. Das Gupta·H. E. Beere·D. A. Ritchie·M. Pepper
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Abstract

We describe a technique to fabricate closely spaced electron-hole bilayers in GaAs-AlGaAs heterostructures. Our technique incorporates a novel method for making shallow contacts to a low density ($<10^{11}cm^{-2}$) 2-dimensional electron gas (2DEG) that do not require annealing. Four terminal measurements on both layers (25nm apart) are possible. Measurements show a hole mobility $μ_{h}>10^{5}{\rm cm}^{2}{\rm V}^{-1}{\rm s}^{-1}$ and an electron mobility $μ_{e}>10^{6}{\rm cm}^{2}{\rm V}^{-1}{\rm s}^{-1}$ at 1.5K. Preliminary drag measurements made down to T=300mK indicate an enhancement of coulomb interaction over the values obtained from a static Random Phase Approximation (RPA) calculation.

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J. A. Keogh, K. Das Gupta, H. E. Beere, D. A. Ritchie, M. Pepper. 2008-07-01. Fabrication of closely spaced, independently contacted Electron-Hole bilayers in GaAs-AlGaAs heterostructures. https://arxiv.org/abs/0807.0106

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