Unsupervised detection of topological phase transitions with a quantum reservoir
Phys. Rev. A 113, 012422 – Published 13 January, 2026
DOI: https://doi.org/10.1103/3c94-9b3g
Abstract
In quantum many-body systems, characterizing topological phase transitions typically requires complex many-body topological invariants, which are costly to compute and measure. Inspired by quantum reservoir computing, we propose an unsupervised quantum phase detection method based on a many-body localized evolution, enabling efficient identification of phase transitions in the extended Su-Schrieffer-Heeger model. The evolved quantum states produce feature distributions under local measurements, which, after simple postprocessing and dimensionality reduction, naturally cluster according to different Hamiltonian parameters. Numerical simulations show that the evolution combined with local measurements can significantly amplify distinctions between quantum states, providing an efficient means to detect topological phase transitions. Our approach requires neither complex measurements nor full density-matrix reconstruction, making it practical and feasible for noisy intermediate-scale quantum devices.
