Nonlocal transport and heating in superconductors under dual-bias conditions

We report on an experimental and theoretical study of nonlocal transport in superconductor hybrid structures, where two normal-metal leads are attached to a central superconducting wire. As a function of voltage bias applied to both normal-metal electrodes, we find surprisingly large nonlocal conductance signals, almost of the same magnitude as the local conductance. We demonstrate that these signals are the result of strong heating of the superconducting wire, and that under symmetric bias conditions, heating mimics the effect of Cooper pair splitting.