Adiabatic quantum pumping at the Josephson frequency.

We analyze theoretically adiabatic quantum pumping through a normal conductor that couples the normal regions of two superconductor - normal-metal - superconductor Josephson junctions. By using the phases of the superconducting order parameter in the superconducting contacts as pumping parameters, we demonstrate that a nonzero pumped charge can flow through the device. The device exploits the evolution of the superconducting phases due to the ac Josephson effect, and can therefore be operated at very high frequency, resulting in a pumped current as large as a few nanoamperes.

Quantum tunneling detection of two-photon and two-electron processes.

We analyze the operation of a quantum tunneling detector coupled to a coherent conductor. We demonstrate that, in a certain energy range, the output of the detector is determined by two-photon processes, two-interacting-electron processes, and the interference of the two. We show how the individual contributions of these processes can be resolved in experiments.

Josephson junctions as threshold detectors for full counting statistics.

We discuss how threshold detectors can be used for a direct measurement of the full distribution of current fluctuations and how to exploit Josephson junctions in this respect. We propose a scheme to characterize the full counting statistics from the current dependence of the escape rate measured. We illustrate the scheme with explicit results for tunnel, diffusive, and quasiballistic mesoscopic conductors.