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arXiv · 1412.4200

A wide-band tunable phase shifter for radio-frequency reflectometry

G. Yin·G. A. D. Briggs·E. A. Laird
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Abstract

Radio-frequency reflectometry of nanodevices requires careful separation of signal quadratures to distinguish dissipative and dispersive contributions to the device impedance. A tunable phase shifter for this purpose is described and characterized. The phase shifter, consisting of a varactor-loaded transmission line, has the necessary tuning range combined with acceptable insertion loss across a frequency band 100 MHz - 1 GHz spanning most radio-frequency experiments. Its operation is demonstrated by demodulating separately the signals due to resistance and capacitance changes in a model device.

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G. Yin, G. A. D. Briggs, E. A. Laird. 2014-12-13. A wide-band tunable phase shifter for radio-frequency reflectometry. https://arxiv.org/abs/1412.4200

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