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arXiv · 1502.06527

Frequency dispersion of nonlinear response of thin superconducting films in Berezinskii-Kosterlitz-Thouless state

Scott Dietrich·William Mayer·Sean Byrnes·Sergey Vitkalov·A. Sergeev·Anthony T. Bollinger·Ivan Bozovic
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Abstract

The effects of microwave radiation on the transport properties of atomically thin $La_{2-x}Sr_xCuO_4$ films were studied in the 0.1-13 GHz frequency range. Resistance changes induced by microwaves were investigated at different temperatures near the superconducting transition. The nonlinear response decreases by several orders of magnitude within a few GHz of a cutoff frequency $\nu_{cut} \approx$ 2 GHz. Numerical simulations that assume an ac response to follow the dc V-I characteristics of the films reproduce well the low frequency behavior, but fail above $\nu_{cut}$. The results indicate that two-dimensional superconductivity is resilient against high-frequency microwave radiation, because vortex-antivortex dissociation is dramatically suppressed in two-dimensional superconducting condensates oscillating at high frequencies.

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Scott Dietrich, William Mayer, Sean Byrnes, Sergey Vitkalov, A. Sergeev, Anthony T. Bollinger, Ivan Bozovic. 2015-02-23. Frequency dispersion of nonlinear response of thin superconducting films in Berezinskii-Kosterlitz-Thouless state. https://doi.org/10.1103/physrevb.91.060506

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