Hong-Ou-Mandel Interference in a temporal-average-inversion-symmetric chain

TL;DR

This paper demonstrates how to implement tunable beam splitters and observe Hong-Ou-Mandel interference in a topological Su-Schrieffer-Heeger chain, highlighting robustness under certain disorders and introducing the concept of temporal-average-inversion-symmetry protection.

Contribution

It introduces a method to realize tunable beam splitters and Hong-Ou-Mandel interference in a topological chain using adiabatic manipulation of edge states, with robustness to specific disorders.

Findings

Achieved tunable beam splitter in a topological chain.

Observed Hong-Ou-Mandel interference and generated NOON states.

Proved robustness of interference under inversion-symmetric disorder.

Abstract

We show how to implement tunable beam splitter and Hong-Ou-Mandel interference in the Su-Schrieffer-Heeger chain by manipulating the topological edge states adiabatically. The boson initially injected in the one end of the chain can be transferred to the two-end with a tunable proportion depends on the dynamical phases accumulated during the adiabatic evolution. We also observe Hong-Ou-Mandel interference via the tunable beam splitter ($50:50$) and achieve a spatially entangled two-particle NOON state. We demonstrate the robustness of our proposal under chiral- and time-reversal-symmetry-preserving disorder. However, the chiral symmetry is scarce for realist system. Therefore, we demonstrate Hong-Ou-Mandel interference are robust to inversion symmetric disorder breaking the chiral symmetry, highlighting the protection of inversion symmetry. More importantly, the inversion symmetry violated by static disorder can be restored for more common situations where disorder becomes time dependent, giving rise to the temporal-average-inversion-symmetry protected Hong-Ou-Mandel interference. Our approach opens a new way to study quantum effects in topological matter with potential applications.