Instrumentation for millimeter-wave magnetoelectrodynamic investigations of low-dimensional conductors and superconductors

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 (similar to 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. (C) 2000 American Institute of Physics. [S0034-6748(00)02301-7].