Automated experimental design for high-probability entanglement generation

TL;DR

This paper introduces an automated design algorithm that optimizes quantum photonic experiments for higher success probabilities and fidelities by accounting for multi-pair emissions, outperforming previous methods.

Contribution

It develops a novel algorithm that explores design topologies and optimizes source parameters to improve entanglement generation in photonic experiments.

Findings

Outperforms previous proposals for heralded Bell, W, and NOON states.

Optimizes source parameters to reduce multi-pair emissions.

Balances fidelity and success probability effectively.

Abstract

Entangled photons are widely used in quantum technologies. Many photonic experiments generate them with probabilistic photon-pair sources that can be modeled as squeeze operators. In practice, these sources are usually treated in the low-gain (perturbative) regime, keeping only the leading single-pair term and neglecting higher-order multi-pair emission events. In pursuit of fidelity, the probability of successful entanglement generation can become extremely small, a tradeoff often ignored. Here we develop an automated design algorithm for quantum experiments to optimize both fidelity and success probability while accounting for higher-order multi-pair emissions. Our discovery algorithm explores different design topologies subject to varying hardware constraints. It optimizes the source parameters to reduce undesired higher-order terms or even benefit from them. The experiments presented outperform previous proposals for widely used states, including heralded Bell states, W states, and NOON states, paving the way for more efficient photonic technologies.