Integrated quantum polariton interferometry

TL;DR

This paper demonstrates how integrated circuits of single exciton-polaritons can be used to create quantum logic gates and perform precise measurements, advancing quantum information processing and metrology with hybrid light-matter systems.

Contribution

It introduces a new approach to quantum polaritonic devices using integrated circuits of propagating single polaritons for quantum computation and metrology.

Findings

Built deterministic quantum logic gates with polaritons.

Showed potential for precise measurement of polariton interactions.

Proposed applications in quantum technologies.

Abstract

Exciton-polaritons are hybrid elementary excitations of light and matter that, thanks to their nonlinear properties, enable a plethora of physical phenomena ranging from room temperature condensation to superfluidity. While polaritons are usually exploited in high density regime, evidence of quantum correlations at the level of few excitations has been recently reported, thus suggesting the possibility of using these systems for quantum information purposes. Here we show that integrated circuits of propagating single polaritons can be arranged to build deterministic quantum logic gates in which the two-particle interaction energy plays a crucial role. Besides showing their prospective potential for photonic quantum computation, we also show that these systems can be exploited for metrology purposes, as for instance to precisely measure the magnitude of the polariton-polariton interaction at the two-body level. In general, our results introduce a novel paradigm for the development of practical quantum polaritonic devices, in which the effective interaction between single polaritonic qubits may provide a unique tool for future quantum technologies.