Electron-hole imbalance in superconductor/normal-metal mesoscopic structures

We analysed the electron-hole or, in other words, branch imbalance (BI) and the related electric potential V_imb which may arise in a mesoscopic superconductor/normal-metal (S/N) structure under non-equilibrium conditions in the presence of a supercurrent. Non-equilibrium conditions can be created in different ways: a) a quasiparticle current flowing between the N reservoirs; b) a temperature gradient between the N reservoirs and no quasiparticle current. It is shown that the voltage V_imb oscillates with the phase difference varphi. In a cross-geometry structure the voltage V_imb arises in the vertical branch and affects the conditions for a transition to the π-state.