Design of nanophotonic circuits for autonomous subsystem quantum error correction

TL;DR

This paper presents a nanophotonic optical network that autonomously corrects quantum errors in a logical qubit using continuous feedback, eliminating the need for discrete syndrome measurements.

Contribution

It introduces a novel design of nanophotonic circuits implementing autonomous quantum error correction based on the Bacon-Shor subsystem code.

Findings

Demonstrates continuous, autonomous error correction in a nanophotonic setup.

Replaces discrete syndrome measurement with optical feedback.

Shows potential for scalable quantum memory implementations.

Abstract

We reapply our approach to designing nanophotonic quantum memories to formulate an optical network that autonomously protects a single logical qubit against arbitrary single-qubit errors. Emulating the 9 qubit Bacon-Shor subsystem code, the network replaces the traditionally discrete syndrome measurement and correction steps by continuous, time-independent optical interactions and coherent feedback of unitarily processed optical fields.