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arXiv · 2110.15817

Integration of Machine Learning with Neutron Scattering: Hamiltonian Tuning in Spin Ice with Pressure

Abstract

Quantum materials research requires co-design of theory with experiments and involves demanding simulations and the analysis of vast quantities of data, usually including pattern recognition and clustering. Artificial intelligence is a natural route to optimise these processes and bring theory and experiments together. Here we propose a scheme that integrates machine learning with high-performance simulations and scattering measurements, covering the pipeline of typical neutron experiments. Our approach uses nonlinear autoencoders trained on realistic simulations along with a fast surrogate for the calculation of scattering in the form of a generative model. We demonstrate this approach in a highly frustrated magnet, Dy$_2$Ti$_2$O$_7$, using machine learning predictions to guide the neutron scattering experiment under hydrostatic pressure, extract material parameters and construct a phase diagram. Our scheme provides a comprehensive set of capabilities that allows direct integration of theory along with automated data processing and provides on a rapid timescale direct insight into a challenging condensed matter system.

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BibTeXRIS

A. M. Samarakoon, D. Alan Tennant, Feng Ye, Qiang Zhang, S. A. Grigera. 2021-10-29. Integration of Machine Learning with Neutron Scattering: Hamiltonian Tuning in Spin Ice with Pressure. https://arxiv.org/abs/2110.15817

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