Frequency-encoded photonic qubits for scalable quantum information processing

TL;DR

This paper introduces spectral LOQC, a novel approach that leverages frequency mismatch in photons for scalable quantum computing, enabling parallel processing and robust optical quantum systems using fiber optics technology.

Contribution

The paper develops spectral LOQC, a new platform that exploits frequency mismatch for quantum information processing, offering scalable, parallel, and wavelength-configurable quantum gates.

Findings

Spectral LOQC enables parallel quantum gate operations on multiple qubit sets.

The approach scales linearly with optical resources, improving efficiency.

It integrates fiber optic technology for robust quantum communication.

Abstract

Among the objectives toward large-scale quantum computation is the quantum interconnect: a device which uses photons to interface qubits that otherwise could not interact. However, current approaches require photons indistinguishable in frequency---a major challenge for systems experiencing different local environments or of different physical compositions altogether. Here we develop an entirely new platform which actually exploits such frequency mismatch for processing quantum information. Labeled "spectral linear optical quantum computation" (spectral LOQC), our protocol offers favorable linear scaling of optical resources and enjoys an unprecedented degree of parallelism, as an arbitrary $N$-qubit quantum gate may be performed in parallel on multiple $N$-qubit sets in the same linear optical device. Not only does spectral LOQC offer new potential for optical interconnects; it also brings the ubiquitous technology of high-speed fiber optics to bear on photonic quantum information, making wavelength-configurable and robust optical quantum systems within reach.