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Instrumentation of a high-sensitivity microwave vector detection system for low-temperature applications

Y. W. Suen·W. H. Hsieh·C. L. Chen·L. C. Li·C. H. Kuan
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Abstract

We present the design and the circuit details of a high-sensitivity microwave vector detection system, which is aiming for studying the low-dimensional electron system embedded in the slots of a coplanar waveguide at low temperatures. The coplanar waveguide sample is placed inside a phase-locked loop; the phase change of the sample may cause a corresponding change in the operation frequency, which can be measured precisely. We also employ a double-pulse modulation on the microwave signals, which comprises a fast pulse modulation for gated averaging and a slow pulse modulation for lock-in detection. In measurements on real samples at low temperatures, this system provides much better resolutions in both amplitude and phase than most of the conventional vector analyzers at power levels below -65 dBm.

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Y. W. Suen, W. H. Hsieh, C. L. Chen, L. C. Li, C. H. Kuan. 2005-04-23. Instrumentation of a high-sensitivity microwave vector detection system for low-temperature applications. https://doi.org/10.1063/1.2006327

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