Frequency Following Imaging of Electric Fields from Resonant Superconducting Devices using a Scanning Near-Field Microwave Microscope

Ashfaq S. Thanawalla; B. J. Feenstra; Wensheng Hu; D. E. Steinhauer; S. K. Dutta; Steven M. Anlage; F. C. Wellstood; Robert B. Hammond

doi:10.1109/77.783670

arXiv · cond-mat/9811141

Frequency Following Imaging of Electric Fields from Resonant Superconducting Devices using a Scanning Near-Field Microwave Microscope

Ashfaq S. Thanawalla·B. J. Feenstra·Wensheng Hu·D. E. Steinhauer·S. K. Dutta·Steven M. Anlage·F. C. Wellstood·Robert B. Hammond

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Abstract

We have developed a scanning near-field microwave microscope that operates at cryogenic temperatures. Our system uses an open-ended coaxial probe with a 200 mm inner conductor diameter and operates from 77 to 300 K in the 0.01-20 GHz frequency range. In this paper, we present microwave images of the electric field distribution above a Tl2Ba2CaCu2O8 microstrip resonator at 77 K, measured at several heights. In addition, we describe the use of a frequency-following circuit to study the influence of the probe on the resonant frequency of the device.

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Ashfaq S. Thanawalla, B. J. Feenstra, Wensheng Hu, D. E. Steinhauer, S. K. Dutta, Steven M. Anlage, F. C. Wellstood, Robert B. Hammond. 1998-11-10. Frequency Following Imaging of Electric Fields from Resonant Superconducting Devices using a Scanning Near-Field Microwave Microscope. https://doi.org/10.1109/77.783670

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