Phase Sensitive Shot Noise in an Andreev Interferometer

B. Reulet, A. A. Kozhevnikov, D. E. Prober, W. Belzig, Yu. V. Nazarov
2003 Physical Review Letters  
We investigate nonequilibrium noise in a diffusive Andreev interferometer, in which currents emerging from two Normal metal/Superconductor (N-S) interfaces can interfere. We observe a modulation of the shot noise when the phase difference between the two N-S interfaces is varied by a magnetic flux. This is the signature of phase-sensitive fluctuations in the normal metal. The effective charge inferred from the shot noise measurement is close to q_eff=2e but shows phase-dependent deviations from
more » ... 2e at finite energy, which we interprete as due to pair correlations. Experimental data are in good agreement with theoretical predictions based on an extended Keldysh Green's function approach.
doi:10.1103/physrevlett.90.066601 pmid:12633314 fatcat:5pzc7x5htneknlhji4ifxtgg6e