arXiv Analytics

Sign in

arXiv:2011.12282 [cond-mat.str-el]AbstractReferencesReviewsResources

Learning Effective Spin Hamiltonian of Quantum Magnet

Sizhuo Yu, Yuan Gao, Bin-Bin Chen, Wei Li

Published 2020-11-24Version 1

Interacting spins in quantum magnet can cooperate and exhibit exotic states like the quantum spin liquid. To explore the materialization of such intriguing states, the determination of effective spin Hamiltonian of the quantum magnet is thus an important, while at the same time, very challenging inverse many-body problem. To efficiently learn the microscopic spin Hamiltonian from the macroscopic experimental measurements, here we propose an unbiased Hamiltonian searching approach that combines various optimization strategies, including the automatic differentiation and Bayesian optimization, etc, with the exact diagonalization and many-body thermal tensor network calculations. We showcase the accuracy and powerfulness by applying it to training thermal data generated from a given spin-chain Hamiltonian, and then to realistic experimental data measured in the spin-chain and triangular-lattice quantum magnetic materials. This automatic Hamiltonian searching constitutes a very promising approach in the studies of the intriguing spin liquid candidate magnets and correlated electron materials in general.