We describe instrumentation for conducting high sensitivity millimeter-wave cavity perturbation measurements over a broad frequency range (40–200 GHz) and in the presence of strong magnetic fields (up to 33 T). A millimeter-wave vector network analyzer (MVNA) acts as a continuously tunable microwave source and phase sensitive detector (8–350 GHz), enabling simultaneous measurements of the complex cavity parameters (resonance frequency and Q value) at a rapid repetition rate (∼10 kHz). We discuss the principle of operation of the MVNA and the construction of a probe for coupling the MVNA to various cylindrical resonator configurations which can easily be inserted into a high field magnet cryostat. We also present several experimental results which demonstrate the potential of the instrument for studies of low-dimensional conducting systems.

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Clarendon Laboratory, University of Oxford, United Kingdom—Dr. John Singleton;
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Institute for Materials Research (IMR), Tohoku University, Japan—Professor M. Motokawa;
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This is due to the high electrical resistivity of SS compared to Ag and Cu. The electrical resistivities at 300 K for SS, electrolytic Cu and Ag are 72, 1.67, and 1.59 mΩ cm, respectively.
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