Quasi-Particle Interferometer Controlled by Andreev Reflection

Summary

We propose a quasiparticle interferometer for experimentally confirming the predicted interaction between the microscopic phase of a quasiparticle and the macroscopic phase of a superconducting state. Andreev reflection at the superconductor- normal-metal (S-N) interface causes phase interaction. The proposed interferometer consists of a Josephson junction and a Y-junction composed of normal electron waveguides. In this setup, the phase interaction due to Andreev reflection affects the quasiparticle interference. Thus the amount of supercurrent flowing through the Josephson junction controls the resistance across the end of a waveguide branch and one electrode of the Josephson junction.