Majorana-induced DC Shapiro steps in topological Josephson junctions
arXiv:2006.05824 · doi:10.1103/PhysRevB.102.140501
Abstract
The demonstration of the non-Abelian properties of Majorana bound states (MBS) is a crucial step toward topological quantum computing. We theoretically investigate how Majorana fusion rules manifest themselves in the current-voltage characteristics of a topological Josephson junction. The junction is built on U-shaped quantum spin Hall edges and hosts a Majorana qubit formed by four MBS. Owing to Majorana fusion rules, inter- and intra-edge couplings among adjacent MBS provide two orthogonal components in the rotation axis of the Majorana qubit. We show that the interplay of the dynamics of the superconductor phase difference and the Majorana qubit governs the Josephson effect. Strikingly, we identify sequential jumps of the voltage across the junction with increasing DC current bias without external AC driving. Its role is replaced by the intrinsic Rabi oscillations of the Majorana qubit. This phenomenon, DC Shapiro steps, is a manifestation of the non-trivial fusion rules of MBS.
4 pages, 3 figures
References in corpus (9)
- Non-Abelian Anyons and Topological Quantum Computation
- Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
- Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices
- Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
- Majorana bound states in a coupled quantum-dot hybrid-nanowire system
- Introduction to topological superconductivity and Majorana fermions
- Majorana qubit decoherence by quasiparticle poisoning
- Number fluctuations of sparse quasiparticles in a superconductor
- Full electrostatic control of quantum interference in an extended trenched Josephson junction