Heralded entangled state generation enhanced by photon addition and subtraction

TL;DR

This paper introduces a probabilistic scheme for generating entangled states using Gaussian sources enhanced by photon addition and subtraction, optimizing parameters for high fidelity and success probability.

Contribution

It presents a new, experimentally feasible method combining Gaussian sources with non-Gaussian operations to improve heralded entanglement generation.

Findings

Photon addition/subtraction enhances non-classicality and performance.

Optimized parameters maximize success probability and fidelity.

Scheme remains stable under realistic imperfections.

Abstract

We propose a heralded entanglement generation scheme based on Gaussian sources enhanced by photon addition and subtraction operations. By combining single-mode squeezing, linear interferometers, and conditional photon-number measurements on ancillary modes, our model can probabilistically generate dual-rail encoded Bell, GHZ, and W states. We systematically optimize the squeezing parameters and interferometer settings to maximize both the heralding success probability and the fidelity with the target states. Our results show that photon addition and subtraction significantly enhance the non-classicality of the output states and improve generation performance, while maintaining computational efficiency comparable to single-photon source models. We further analyze the robustness of the scheme under parameter perturbations and find that its performance remains stable under realistic experimental imperfections. This work provides a versatile and experimentally feasible framework for scalable heralded entanglement generation using Gaussian resources with non-Gaussian operations.