Bolometric technique for high-resolution broadband microwave spectroscopy of ultra-low-loss samples

P. J. Turner; D. M. Broun; Saeid Kamal; M. E. Hayden; J. S. Bobowski; R. Harris; D. C. Morgan; J. S. Preston; D. A. Bonn; W. N. Hardy

doi:10.1063/1.1633001

arXiv · cond-mat/0307340

Bolometric technique for high-resolution broadband microwave spectroscopy of ultra-low-loss samples

P. J. Turner·D. M. Broun·Saeid Kamal·M. E. Hayden·J. S. Bobowski·R. Harris·D. C. Morgan·J. S. Preston·D. A. Bonn·W. N. Hardy

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Abstract

A novel low temperature bolometric method has been devised and implemented for high-precision measurements of the microwave surface resistance of small single-crystal platelet samples having very low absorption, as a continuous function of frequency. The key to the success of this non-resonant method is the in-situ use of a normal metal reference sample that calibrates the absolute rf field strength. The sample temperature can be controlled independently of the 1.2 K liquid helium bath, allowing for measurements of the temperature evolution of the absorption. However, the instrument's sensitivity decreases at higher temperatures, placing a limit on the useful temperature range. Using this method, the minimum detectable power at 1.3 K is 1.5 pW, corresponding to a surface resistance sensitivity of $\approx$1 $\mu\Omega$ for a typical 1 mm$\times$1 mm platelet sample.

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P. J. Turner, D. M. Broun, Saeid Kamal, M. E. Hayden, J. S. Bobowski, R. Harris, D. C. Morgan, J. S. Preston, D. A. Bonn, W. N. Hardy. 2003-07-15. Bolometric technique for high-resolution broadband microwave spectroscopy of ultra-low-loss samples. https://doi.org/10.1063/1.1633001

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