Quantum Phase Recognition via Quantum Attention Mechanism

TL;DR

This paper introduces a hybrid quantum-classical attention model that efficiently recognizes quantum phases in many-body systems by capturing correlation structures with minimal training data, demonstrating robustness and scalability.

Contribution

It presents a novel quantum attention mechanism combining swap tests and quantum circuits for ground-state classification, advancing quantum phase recognition methods.

Findings

High classification accuracy with less than 100 training samples

Robustness against training set variations

Captures phase-sensitive features and physical length scales

Abstract

Quantum phase transitions in many-body systems are fundamentally characterized by complex correlation structures, which pose computational challenges for conventional methods in large systems. To address this, we propose a hybrid quantum-classical attention model. This model uses an attention mechanism, realized through swap tests and a parameterized quantum circuit, to extract correlations within quantum states and perform ground-state classification. Benchmarked on the cluster-Ising model with system sizes of 9 and 15 qubits, the model achieves high classification accuracy with less than 100 training data and demonstrates robustness against variations in the training set. Further analysis reveals that the model successfully captures phase-sensitive features and characteristic physical length scales, offering a scalable and data-efficient approach for quantum phase recognition in complex many-body systems.