A Hybrid Approach to Mitigate Errors in Linear Photonic Bell-State Measurement for Quantum Interconnects

TL;DR

This paper presents a hybrid detection scheme combining on-off and homodyne detection to improve Bell-state measurement fidelity in optical quantum information processing, addressing limitations of photon-number resolution.

Contribution

A novel hybrid detection approach for Bell-state measurement that enhances fidelity and outperforms photon-number resolving detectors in quantum communication tasks.

Findings

Hybrid scheme achieves higher fidelity in quantum teleportation.

Strong advantage over photon-number resolving detectors across parameters.

Applicable to quantum state engineering and interconnects.

Abstract

Optical quantum information processing critically relies on Bell-state measurement, a ubiquitous operation for quantum communication and computing. Its practical realization involves the interference of optical modes and the detection of a single photon in an indistinguishable manner. Yet, in the absence of efficient photon-number resolution capabilities, errors arise from multi-photon components, decreasing the overall process fidelity. Here, we introduce a novel hybrid detection scheme for Bell-state measurement, leveraging both on-off single-photon detection and quadrature conditioning via homodyne detection. We derive explicit fidelities for quantum teleportation and entanglement swapping processes employing this strategy, demonstrating its efficacy. We also compare with photon-number resolving detectors and find a strong advantage of the hybrid scheme in a wide range of parameters. This work provides a new tool for linear optics schemes, with applications to quantum state engineering and quantum interconnects.