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arXiv · 2006.12409

Heterostructure design to achieve high quality, high density GaAs 2D electron system with $g$-factor tending to zero

Yoon Jang Chung·S. Yuan·Yang Liu·K. W. Baldwin·K. W. West·M. Shayegan·L. N. Pfeiffer
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Abstract

Hydrostatic pressure is a useful tool that can tune several key parameters in solid state materials. For example, the Land\'e $g$-factor in GaAs two-dimensional electron systems (2DESs) is expected to change from its bulk value $g\simeq-0.44$ to zero and even to positive values under a sufficiently large hydrostatic pressure. Although this presents an intriguing platform to investigate electron-electron interaction in a system with $g=0$, studies are quite limited because the GaAs 2DES density decreases significantly with increasing hydrostatic pressure. Here we show that a simple model, based on pressure-dependent changes in the conduction band alignment, quantitatively explains this commonly observed trend. Furthermore, we demonstrate that the decrease in the 2DES density can be suppressed by more than a factor of 3 through an innovative heterostructure design.

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Yoon Jang Chung, S. Yuan, Yang Liu, K. W. Baldwin, K. W. West, M. Shayegan, L. N. Pfeiffer. 2020-06-22. Heterostructure design to achieve high quality, high density GaAs 2D electron system with $g$-factor tending to zero. https://doi.org/10.1063/5.0013938

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