20 февраля 2024 г. в 13:00 состоится семинар ИТПЭ РАН лаборатории Теоретической электродинамики конденсированного состояния (под рук. д.ф.-м.н. А.Л. Рахманова)
Адрес: ул. Красноказарменная, 17а (фактически находится на ул. Лапина 17а), комн. 513
Автор доклада: Олег Лычковский
Тема доклада: Quantum dynamics in one and two dimensions via recursion method
Аннотация:
Recursion method is a technique to solve coupled Heisenberg equations in a tridiagonal operator basis constructed via Lanczos algorithm. We report an implementation of the recursion method that addresses quantum many-body dynamics in the nonperturbative regime. The implementation has two key ingredients: a computer-algebraic routine for symbolic calculation of nested commutators and a procedure to extrapolate the sequence of Lanczos coefficients according to the universal operator growth hypothesis. We apply the method to calculate infinite-temperature correlation functions for spin-1/2 systems on one- and two-dimensional lattices. In two dimensions the accessible timescale is large enough to essentially embrace the relaxation to equilibrium. The method allows one to accurately calculate transport coefficients. As an illustration, we compute the diffusion constant for the transverse-field Ising model on a square lattice. The talk will be based on arXiv 2401.17211.