Bang-bang preparation of quantum many-body ground states in two dimensions: optimization of the algorithm with a two-dimensional tensor network

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Zhang, Yintai, Dziarmaga, Jacek
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910633654484992
author Zhang, Yintai
Dziarmaga, Jacek
author_facet Zhang, Yintai
Dziarmaga, Jacek
contents A bang-bang (BB) algorithm prepares the ground state of a two-dimensional (2D) quantum many-body Hamiltonian $H=H_1+H_2$ by evolving an initial product state alternating between $H_1$ and $H_2$. We use the neighborhood tensor update to simulate the BB evolution with an infinite pair-entangled projected state (iPEPS). The alternating sequence is optimized with the final energy as a cost function. The energy is calculated with the tangent space methods for the sake of their stability. The method is benchmarked in the 2D transverse field quantum Ising model near its quantum critical point against a ground state obtained by variational optimization of the iPEPS. The optimal BB sequence differs non-perturbatively from a sequence simulating quantum annealing or adiabatic preparation (AP) of the ground state. The optimal BB energy converges with the number of bangs much faster than the optimal AP energy.
format Preprint
id arxiv_https___arxiv_org_abs_2401_09158
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Bang-bang preparation of quantum many-body ground states in two dimensions: optimization of the algorithm with a two-dimensional tensor network
Zhang, Yintai
Dziarmaga, Jacek
Quantum Physics
Other Condensed Matter
Computational Physics
A bang-bang (BB) algorithm prepares the ground state of a two-dimensional (2D) quantum many-body Hamiltonian $H=H_1+H_2$ by evolving an initial product state alternating between $H_1$ and $H_2$. We use the neighborhood tensor update to simulate the BB evolution with an infinite pair-entangled projected state (iPEPS). The alternating sequence is optimized with the final energy as a cost function. The energy is calculated with the tangent space methods for the sake of their stability. The method is benchmarked in the 2D transverse field quantum Ising model near its quantum critical point against a ground state obtained by variational optimization of the iPEPS. The optimal BB sequence differs non-perturbatively from a sequence simulating quantum annealing or adiabatic preparation (AP) of the ground state. The optimal BB energy converges with the number of bangs much faster than the optimal AP energy.
title Bang-bang preparation of quantum many-body ground states in two dimensions: optimization of the algorithm with a two-dimensional tensor network
topic Quantum Physics
Other Condensed Matter
Computational Physics
url https://arxiv.org/abs/2401.09158