ar X iv : 0 70 7 . 42 37 v 2 [ co nd - m at . s up r - co n ] 2 3 M ar 2 00 8 Fluctuation spectroscopy of granularity in superconducting structures
نویسنده
چکیده
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.
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