Fluctuation spectroscopy of granularity in superconducting structures.
We suggest to use "fluctuation spectroscopy" as a method to detect granularity in a disordered metal close to a superconducting transition. We show that with lowering temperature T the resistance R(T) of a system of relatively large grains initially grows due to the fluctuation suppression of the one-electron tunneling but decreases with further lowering T due to the coherent charge transfer of the fluctuation Cooper pairs. Under certain conditions, such a maximum in R(T) turns out to be sensitive to weak magnetic fields due to a novel Maki-Thompson-type mechanism.
Lerner
I V
IV
School of Physics and Astronomy, University of Birmingham, Edgbaston, B15 2TT Birmingham, United Kingdom.
Varlamov
A A
AA
Vinokur
V M
VM