Two-Component Coulomb Glass in Insulators with Local Attraction

by Prof. Vikram Tripathi (TIFR)

Wednesday 4 Jul 2012, 14:30 → 15:30 Asia/Kolkata

A304 (Colaba Campus)

I will review the well-known arguments of Efros and Shklovskii on how long-range Coulomb interaction of charges in a strongly disordered insulator give rise to a Coulomb-gap in the density of states and a stretched-exponential temperature dependence of resistivity. Thereafter I will discuss how these results are modified if two-particle processes such as Cooper pair tunnelling are also significant. Of particular interest is the prediction of a non-monotonous temperature or magnetic field dependence of resistivity. Experimental motivation for this work comes from the magnetoresistance peak seen in strongly disordered superconductors. Reference: J. Mitchell, A. Gangopadhyay, V. Galitski, and M. Müller, Phys. Rev. B 85, 195141 (2012)