Quenching the superconducting state of cuprate compounds with electric currents: a variational study.
We investigate the properties of cuprate superconductors subject to applied current, using modified Gutzwiller projected d-wave BCS states. The parent states include quasiparticle and quasihole pockets, of variationally determined size, generated by the current. We identify two different mechanisms for the destruction of superconductivity at the critical current: at high hole doping (x≳0.15) the pockets grow and completely destroy the gap, in a BCS-like mechanism; in the underdoped regime, the superfluid stiffness vanishes at a maximal phase twist with pairing still intact. This result is indicative of a pseudogapped "normal" state which retains pairing correlations. The critical current as a function of doping displays a dome shape, similar to Tc. We predict unique signatures of the current induced Fermi pockets that can be seen in angle-resolved photoemission spectroscopy.
Goren
Lilach
L
Department of Condensed Matter Physics, The Weizmann Institute of Science, 76100 Rehovot, Israel.
Altman
Ehud
E