High-sensitivity microwave vector detection at extremely low-power levels for low-dimensional electron systems

W. H. Hsieh; C. H. Kuan; Y. W. Suen; S. Y. Chang; L. C. Li B. C. Lee; C. P. Lee

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High-sensitivity microwave vector detection at extremely low-power levels for low-dimensional electron systems

W. H. Hsieh·C. H. Kuan·Y. W. Suen·S. Y. Chang·L. C. Li B. C. Lee·C. P. Lee

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Abstract

We present a high-sensitivity microwave vector detection system for studying the low-dimensional electron system embedded in the gaps of a coplanar waveguide at low temperatures. Using this system, we have achieved 0.005% and 0.001\textdegree resolutions in amplitude and phase variations, respectively, at 10 GHz in a magnetotransport measurement on a quantum-wire array with an average signal power less than $-$75 dBm into the sample at 0.3 K. From the measured phase variation, we can distinguish a very tiny change in the induced dipole moment of each quantum wire.

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W. H. Hsieh, C. H. Kuan, Y. W. Suen, S. Y. Chang, L. C. Li B. C. Lee, C. P. Lee. 2005-04-27. High-sensitivity microwave vector detection at extremely low-power levels for low-dimensional electron systems. https://arxiv.org/abs/cond-mat/0504714

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