DC transport in a dissipative superconducting quantum point contact

Visuri, A.-M.*; Mohan, J.*; Uchino, Shun   ; Huang, M.-Z.*; Esslinger, T.*; Giamarchi, T.*

We study the current-voltage characteristics of a superconducting junction with particle losses at the contacts. We adopt the Keldysh formalism to compute the steady-state current for varying transmission of the contact. In the low transmission regime, the dissipation leads to an enhancement of the current at low bias, a nonmonotonic dependence of current on dissipation, and the emergence of new structures in the current-voltage curves. The effect of dissipation by particle loss is found to be qualitatively different from that of a finite temperature and a finite inelastic scattering rate in the reservoirs.