Dephasing in semiconductor-superconductor structures by coupling to a voltage probe

We study dephasing in semiconductor-superconductor structures caused by cou pling to a voltage probe. We consider structures where the semiconductor co nsists of Two scattering regions between which partial dephasing is possibl e. As a particular example we consider a situation with a double barrier ju nction in the normal region. For a single-mode system we study the conducta nce both as a function of the position of the Fermi level and as a function of the barrier transparency. At resonance, where the double barrier is ful ly transparent, we study the suppression of the ideal factor-of-two enhance ment of the conductance when a finite coupling to the voltage probe is take n into account. (C) 2000 Academic Press.