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Evidence of many-body localization in 2D from quantum Monte Carlo simulation

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 نشر من قبل Nyayabanta Swain
 تاريخ النشر 2021
  مجال البحث فيزياء
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We use the stochastic series expansion quantum Monte Carlo method, together with the eigenstate-to-Hamiltonian mapping approach, to map the localized ground states of the disordered two-dimensional Heisenberg model, to excited states of a target Hamiltonian. The localized nature of the ground state is established by studying the spin stiffness, local entanglement entropy, and local magnetization. This construction allows us to define many body localized states in an energy resolved phase diagram thereby providing concrete numerical evidence for the existence of a many-body localized phase in two dimensions.



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