← Back to search

Josephson coupling through a quantum dot

A. V. Rozhkov, Daniel P. Arovas, F. Guinea

DOI 10.1103/PhysRevB.64.233301 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

We derive, via fourth-order perturbation theory, an expression for the Josephson current through a gated interacting quantum dot. We analyze our expression for two different models of the superconductor-dot-superconductor (SDS) system. When the matrix elements connecting dot and leads are featureless constants, we compute the Josephson coupling Jc as a function of the gate voltage and Coulomb interaction. In the limit of a diffusive dot, we compute the probability distribution P(Jc) of Josephson couplings. In both cases, π junction behavior (Jc<0) is possible, and is not simply dependent on the parity of the dot occupancy.

Similar papers