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arXiv · 2106.12791

Robust Identification of Topological Phase Transition by Self-Supervised Machine Learning Approach

Abstract

We propose a systematic methodology to identify the topological phase transition through a self-supervised machine learning model, which is trained to correlate system parameters to the non-local observables in time-of-flight experiments of ultracold atoms. Different from the conventional supervised learning approach, where the predicted phase transition point is very sensitive to the training region and data labeling, our self-supervised learning approach identifies the phase transition point by the largest deviation of the predicted results from the known system parameters and by the highest confidence through a systematic shift of the training regions. We demonstrate the robust application of this approach results in various 1D and 2D exactly solvable models, using different input features (time-of-flight images, spatial correlation function or density-density correlation function). As a result, our self-supervised approach should be a very general and reliable method for many condensed matter or solid-state systems to observe new states of matters solely based on experimental measurements, even without a priori knowledge of the phase transition models.

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Chi-Ting Ho, Daw-Wei Wang. 2021-06-24. Robust Identification of Topological Phase Transition by Self-Supervised Machine Learning Approach. https://doi.org/10.1088/1367-2630%2Fac1709

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