Direct Microwave Measurement of Andreev-Bound-State Dynamics in a Semiconductor-Nanowire Josephson Junction

作者：Hays M^*; de Lange G; Serniak K; van Woerkom D J; Bouman D; Krogstrup P; Nygard J; Geresdi A; Devoret M H^*

来源：Physical Review Letters, 2018, 121(4): 047001.

DOI：10.1103/PhysRevLett.121.047001

The modem understanding of the Josephson effect in mesosopic devices derives from the physics of Andreev bound states, fermionic modes that are localized in a superconducting weak link. Recently, Josephson junctions constructed using semiconducting nanowires have led to the realization of superconducting qubits with gate-tunable Josephson energies. We have used a microwave circuit QED architecture to detect Andreev bound states in such a gate-tunable junction based on an aluminum-proximitized indium arsenide nanowire. We demonstrate coherent manipulation of these bound states, and track the bound-state fermion parity in real time. Individual parity-switching events due to nonequilibrium quasiparticles are observed with a characteristic timescale T-parity = 160 +/- 10 mu s. The T-parity of a topological nanowire junction sets a lower bound on the bandwidth required for control of Majorana bound states.

• 出版日期2018-7-23