Deterministic generation of frequency-bin-encoded microwave photons

TL;DR

This paper demonstrates a method for deterministic frequency-bin encoding of microwave photons in superconducting circuits, enabling high-fidelity quantum state transfer with error detection for distributed quantum computing.

Contribution

It introduces a novel frequency-bin encoding protocol for microwave photons and experimentally achieves high process fidelity, improving quantum communication reliability.

Findings

Achieved 90.4% process fidelity in encoding

Demonstrated deterministic encoding of quantum information

Enabled photon loss detection for reliable quantum transfer

Abstract

A distributed quantum computing network requires a quantum communication channel between spatially separated processing units. In superconducting circuits, such a channel can be implemented based on propagating microwave photons to encode and transfer quantum information between an emitter and a receiver. However, traveling microwave photons can be lost during the transmission, leading to the failure of information transfer. Heralding protocols can be used to detect such photon losses. In this work, we propose such a protocol and experimentally demonstrate a frequency-bin encoding method of microwave photonic modes using superconducting circuits. We deterministically encode the quantum information from a superconducting qubit by simultaneously emitting its information into two photonic modes at different frequencies, with a process fidelity of 90.4%. The frequency-bin-encoded photonic modes can be used, at the receiver processor, to detect the occurrence of photon loss. Our work thus provides a reliable method to implement high-fidelity quantum state transfer in a distributed quantum computing network, incorporating error detection to enhance performance and accuracy.