Preparing Spin Squeezed States via Adaptive Genetic Algorithm

TL;DR

This paper presents an adaptive genetic algorithm approach for optimizing control sequences to generate high-fidelity spin-squeezed quantum states, outperforming traditional methods even in noisy, dissipative environments.

Contribution

The study introduces a novel adaptive genetic algorithm for quantum state preparation, demonstrating its effectiveness and robustness compared to existing control protocols and reinforcement learning.

Findings

Achieves spin-squeezed states with fidelity over 0.99.

Demonstrates scalable performance under dissipation and noise.

Outperforms constant control and reinforcement learning methods.

Abstract

We introduce a novel strategy employing an adaptive genetic algorithm (GA) for iterative optimization of control sequences to generate quantum nonclassical states. Its efficacy is demonstrated by preparing spin-squeezed states in an open collective spin model governed by a linear control field. Inspired by Darwinian evolution, the algorithm iteratively refines control sequences using crossover, mutation, and elimination strategies, starting from a coherent spin state within a dissipative and dephasing environment. We rigorously benchmark our method against constant control protocols and reinforcement learning, demonstrating competitive and robust performance. Furthermore, we showcase the GA's versatility by directly optimizing for metrologically relevant squeezing, achieving scalable performance, even in the presence of dissipation and thermal noise. The proposed strategy demonstrates a high state-preparation fidelity, exceeding 0.99, and provides a long time window for maintaining the spin squeezed state, even under dissipative conditions. We discuss feasible experimental implementations and potential extensions to alternative quantum systems, and the adaptability of the GA module. This research establishes the foundation for utilizing GA-like strategies in controlling quantum systems and achieving desired nonclassical states.