An opto-magneto-mechanical quantum interface between distant superconducting qubits

TL;DR

This paper proposes a novel opto-magneto-mechanical system enabling high-fidelity microwave-to-optical quantum information transfer between distant superconducting qubits, advancing quantum internet technology.

Contribution

It introduces a concrete system design for coherent microwave-optical quantum interconnection using magnetic modulation of a mechanical oscillator.

Findings

Predicted transfer fidelity up to 80% with current parameters.

System enables coherent quantum information exchange over long distances.

Analyzes effects of optical fiber loss on transfer fidelity.

Abstract

A quantum internet, where widely separated quantum devices are coherently connected, is a fundamental vision for local and global quantum information networks and processing. Superconducting quantum devices can now perform sophisticated quantum engineering locally on chip and a detailed method to achieve coherent optical quantum interconnection between distant superconducting devices is a vital, but highly challenging, goal. We describe a concrete opto-magneto-mechanical system that can interconvert microwave-to-optical quantum information with high fidelity. In one such node we utilise the magnetic fields generated by the supercurrent of a flux qubit to coherently modulate a mechanical oscillator that is part of a high-Q optical cavity to achieve high fidelity microwave-to-optical quantum information exchange. We analyze the transfer between two spatially distant nodes connected by an optical fibre and using currently accessible parameters we predict that the fidelity of transfer could be as high as $\sim 80\%$, even with significant loss.