Single-photon non-reciprocity with an integrated magneto-optical isolator

TL;DR

This paper demonstrates a silicon nitride-based magneto-optical isolator that exhibits single-photon non-reciprocal transmission with verified quantum coherence, advancing integrated quantum photonic circuits.

Contribution

It introduces an on-chip magneto-optical isolator capable of single-photon non-reciprocal transmission and verifies its quantum coherence properties.

Findings

Achieved 12.33 dB isolation ratio for single photons

Verified quantum coherence via high-visibility interference

Demonstrated potential for integrated quantum photonic circuits

Abstract

Non-reciprocal photonic devices are essential components of classical optical information processing. It is interesting and important to investigate their feasibility in the quantum world. In this work, the quantum properties of an on-chip silicon nitride (SiN)-based magneto-optical (MO) isolator were studied using a single-photon non-reciprocal dynamical transmission experiment. The measured isolation ratio for single photons achieved was 12.33 dB, which proved the functionality of our on-chip isolator. The quantum coherence of the passing single photons was further verified using high-visibility quantum interference. Our work will promote on-chip isolators within the integrated quantum circuits and help introduce novel phenomena in quantum information processes.