Measuring electron energy distribution by current fluctuations

A recent concept of local noise sensor is extended to measure the energy resolved electronic energy distribution $f(\varepsilon)$ at a given location inside a non-equilibrium normal metal interconnect. A quantitative analysis of $f(\varepsilon)$ is complicated because of a nonlinear differential resistance of the noise sensor, represented by a diffusive InAs nanowire. Nevertheless, by comparing the non-equilibrium results with reference equilibrium measurements, we conclude that $f(\varepsilon)$ is indistinguishable from the Fermi distribution

Efficient Cooper Pair Splitting Without Coulomb Blockade

For the three-terminal NSN device with single-mode normal terminals and without Coulomb blockade, we propose an approach which allows us to consistently characterize the device operation as that of a Cooper pair splitter in terms of scattering matrix elements as well as in terms of measurable quantities. The obtained explicit expression for the splitting probability notably contains the two-particle interference term not available from conductance measurements. We show that splitting doesn't necessarily rely on crossed Andreev reflection thus allowing for the unit efficiency at zero energy. Our results imply that the current cross-correlator generally doesn't provide definite measure of splitting.Comment: 6 pages + 10 pages Supplemental Materia