Multi-particle interferometry in the time-energy domain with localized topological quasiparticles

TL;DR

This paper introduces multi-particle interferometry protocols in the time-energy domain to detect and manipulate localized topological quasiparticles, specifically Majorana bound states, using quantum dot setups.

Contribution

It presents a novel interferometry method using quantum dots coupled to topological systems to identify and control topological quasiparticles via characteristic interference patterns.

Findings

Detection of robust, quantized $\pi$ phase shifts indicating topological quasiparticles

Distinct interference patterns for topologically trivial and nontrivial systems

Potential for quantum state manipulation through post-selection

Abstract

We propose multi-particle interference protocols in the time-energy domain which are able to probe localized topological quasiparticles. Using a set of quantum dots tunnel-coupled to a topologically nontrivial system, the time dependence of the dot level energies defines a many-body interferometry platform which (to some extent) is similar to the Hong-Ou-Mandel (HOM) interferometer. We demonstrate that for a superconducting island harboring at least four Majorana bound states, the probability distribution of the final dot occupation numbers will exhibit a characteristic interferometric pattern with robust and quantized $\pi$ phase shifts. This pattern is shown to be qualitatively different for topologically trivial variants of our setup. Apart from identifying the presence of topological quasiparticles, the interferometer can be used to manipulate the quantum state in the topologically nontrivial sector by means of post-selection.