Momentum-resolved time evolution with matrix product states
Strongly Correlated Electrons
2022-06-08 v2 Quantum Physics
Abstract
We introduce a method based on matrix product states (MPS) for computing spectral functions of (quasi) one-dimensional spin chains, working directly in momentum space in the thermodynamic limit. We simulate the time evolution after applying a momentum operator to an MPS ground state by working with the momentum superposition of a window MPS. We show explicitly for the spin-1 Heisenberg chain that the growth of entanglement is smaller in momentum space, even inside a two-particle continuum, such that we can attain very accurate spectral functions with relatively small bond dimension. We apply our method to compute spectral lineshapes of the gapless XXZ chain and the square-lattice J1-J2 Heisenberg model on a six-leg cylinder.
Cite
@article{arxiv.2201.07314,
title = {Momentum-resolved time evolution with matrix product states},
author = {Maarten Van Damme and Laurens Vanderstraeten},
journal= {arXiv preprint arXiv:2201.07314},
year = {2022}
}