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Resistance behavior near the magnetic-field-tuned quantum transition in superconducting amorphous In-O films

V. F. Gantmakher·M. V. Golubkov·V. T. Dolgopolov·G. E. Tsydynzhapov·A. A. Shashkin
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Abstract

We have studied the magnetic-field-tuned superconductivity destroying quantum transition in amorphous In-O films with the onset of superconductivity in zero field at about 2 K. At temperatures down to 30 mK the critical resistance R_c=R(T,B_c) has been found to change approximately linearly with temperature, which is in contradiction to a standard description where zero slope dR_c/dT = 0 is assumed near T=0. To make the data R(T,B) collapse in the vicinity of transition against scaling variable (B-B_c)/T^{1/y}, one has either to allow for the intrinsic temperature dependence of R_c or to postulate the critical field B_c to be temperature-dependent B_c(T)-B_c(0)~T^{1+1/y}. We find that the state on the high-field side of the transition can be both insulating and metallic and we determine the critical index y=1.2.

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V. F. Gantmakher, M. V. Golubkov, V. T. Dolgopolov, G. E. Tsydynzhapov, A. A. Shashkin. 1998-06-20. Resistance behavior near the magnetic-field-tuned quantum transition in superconducting amorphous In-O films. https://arxiv.org/abs/cond-mat/9806244

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