Distilling Quantum Entanglement via Mode-Matched Filtering

TL;DR

This paper introduces a novel method for quantum entanglement distillation using mode-matched filtering, effectively purifying entangled photons in photonic systems affected by mode impurities and noise.

Contribution

It presents a new entanglement distillation technique applicable to photonic systems with mode impurities, enhancing entanglement purity in practical quantum communication.

Findings

Effective purification of telecom-band entanglement

Significant reduction of Raman-scattering noise

Applicable to fiber-based quantum systems

Abstract

We propose a new avenue towards distillation of quantum entanglement that is implemented by directly passing the entangled qubits through a mode-matched filter. This approach can be applied to a common class of entanglement impurities appearing in photonic systems where the impurities inherently occupy different spatiotemporal modes than the entangled qubits. As a specific application, we show that our method can be used to significantly purify the telecom-band entanglement generated via the Kerr nonlinearity in single-mode fibers where a substantial amount of Raman-scattering noise is concomitantly produced.