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arXiv · 1709.06125

Impact of silicon doping on low frequency charge noise and conductance drift in GaAs/AlGaAs nanostructures

S. Fallahi·J. R. Nakamura·G. C. Gardner·M. M. Yannell·M. J. Manfra
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Abstract

We present measurements of low frequency charge noise and conductance drift in modulation doped GaAs/AlGaAs heterostructures grown by molecular beam epitaxy in which the silicon doping density has been varied from $2.4\times 10^{18} cm^{-3}$ (critically doped) to $6.0\times 10^{18} cm^{-3}$ (overdoped). Quantum point contacts were used to detect charge fluctuations. A clear reduction of both short time scale telegraphic noise and long time scale conductance drift with decreased doping density was observed. These measurements indicate that the {\it neutral} doping region plays a significant role in charge noise and conductance drift.

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S. Fallahi, J. R. Nakamura, G. C. Gardner, M. M. Yannell, M. J. Manfra. 2017-09-18. Impact of silicon doping on low frequency charge noise and conductance drift in GaAs/AlGaAs nanostructures. https://doi.org/10.1103/physrevapplied.9.034008

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