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Parallel Quantum-Point-Contacts as High-Frequency-Mixers

A. G. C. Haubrich·D. A. Wharam·H. Kriegelstein·S. Manus·A. Lorke·A. C. Gossard·J. P. Kotthaus
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Abstract

We present the results of high-frequency mixing experiments performed upon parallel quantum point-contacts defined in the two-dimensional electron gas of an Al_{x}Ga_{1-x}As/GaAs-heterostructure. The parallel geometry, fabricated using a novel double-resist technology, enables the point-contact device to be impedance matched over a wide frequency range and, in addition, increases the power levels of the mixing signal while simultaneously reducing the parasitic source-drain capacitance. Here, we consider two parallel quantum point-contact devices with 155 and 110 point-contacts respectively; both devices operated successfully at liquid helium and liquid nitrogen temperatures with a minimal conversion loss of 13 dB.

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A. G. C. Haubrich, D. A. Wharam, H. Kriegelstein, S. Manus, A. Lorke, A. C. Gossard, J. P. Kotthaus. 1997-06-02. Parallel Quantum-Point-Contacts as High-Frequency-Mixers. https://doi.org/10.1063/1.119139

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