Speedup of the quantum adiabatic algorithm using delocalization catalysis

We propose a method to speed up the quantum adiabatic algorithm using catalysis by many-body delocalization. This is applied to random-field antiferromagnetic Ising spin models. The algorithm is catalyzed in such a way that the evolution approximates a Heisenberg model in the middle of its course, a...

Full description

Bibliographic Details
Main Authors: Chenfeng Cao, Jian Xue, Nic Shannon, Robert Joynt
Format: Article
Language:English
Published: American Physical Society 2021-01-01
Series:Physical Review Research
Online Access:http://doi.org/10.1103/PhysRevResearch.3.013092
_version_ 1797211165902766080
author Chenfeng Cao
Jian Xue
Nic Shannon
Robert Joynt
author_facet Chenfeng Cao
Jian Xue
Nic Shannon
Robert Joynt
author_sort Chenfeng Cao
collection DOAJ
description We propose a method to speed up the quantum adiabatic algorithm using catalysis by many-body delocalization. This is applied to random-field antiferromagnetic Ising spin models. The algorithm is catalyzed in such a way that the evolution approximates a Heisenberg model in the middle of its course, and the model is in a delocalized phase. We show numerically that we can speed up the standard algorithm for finding the ground state of the random-field Ising model using this idea. We also demonstrate that the speedup is due to gap amplification, even though the underlying model is not frustration-free. The crossover to speedup occurs at roughly the value of the interaction which is known to be the critical one for the delocalization transition. We also calculate the participation ratio and entanglement entropy as a function of time: Their time dependencies indicate that the system is exploring more states and that they are more entangled than when there is no catalyst. Together, all these pieces of evidence demonstrate that the speedup is related to delocalization. Even though only relatively small systems can be investigated, the evidence suggests that the scaling of the method with system size is favorable. Our method is illustrated by experimental results from a small online IBM quantum computer, showing how to verify the method in future as such machines improve. The cost of the catalytic method compared with the standard algorithm is only a constant factor.
first_indexed 2024-04-24T10:22:10Z
format Article
id doaj.art-f12d2e07cb3e4cb98a497873038c22fc
institution Directory Open Access Journal
issn 2643-1564
language English
last_indexed 2024-04-24T10:22:10Z
publishDate 2021-01-01
publisher American Physical Society
record_format Article
series Physical Review Research
spelling doaj.art-f12d2e07cb3e4cb98a497873038c22fc2024-04-12T17:06:52ZengAmerican Physical SocietyPhysical Review Research2643-15642021-01-013101309210.1103/PhysRevResearch.3.013092Speedup of the quantum adiabatic algorithm using delocalization catalysisChenfeng CaoJian XueNic ShannonRobert JoyntWe propose a method to speed up the quantum adiabatic algorithm using catalysis by many-body delocalization. This is applied to random-field antiferromagnetic Ising spin models. The algorithm is catalyzed in such a way that the evolution approximates a Heisenberg model in the middle of its course, and the model is in a delocalized phase. We show numerically that we can speed up the standard algorithm for finding the ground state of the random-field Ising model using this idea. We also demonstrate that the speedup is due to gap amplification, even though the underlying model is not frustration-free. The crossover to speedup occurs at roughly the value of the interaction which is known to be the critical one for the delocalization transition. We also calculate the participation ratio and entanglement entropy as a function of time: Their time dependencies indicate that the system is exploring more states and that they are more entangled than when there is no catalyst. Together, all these pieces of evidence demonstrate that the speedup is related to delocalization. Even though only relatively small systems can be investigated, the evidence suggests that the scaling of the method with system size is favorable. Our method is illustrated by experimental results from a small online IBM quantum computer, showing how to verify the method in future as such machines improve. The cost of the catalytic method compared with the standard algorithm is only a constant factor.http://doi.org/10.1103/PhysRevResearch.3.013092
spellingShingle Chenfeng Cao
Jian Xue
Nic Shannon
Robert Joynt
Speedup of the quantum adiabatic algorithm using delocalization catalysis
Physical Review Research
title Speedup of the quantum adiabatic algorithm using delocalization catalysis
title_full Speedup of the quantum adiabatic algorithm using delocalization catalysis
title_fullStr Speedup of the quantum adiabatic algorithm using delocalization catalysis
title_full_unstemmed Speedup of the quantum adiabatic algorithm using delocalization catalysis
title_short Speedup of the quantum adiabatic algorithm using delocalization catalysis
title_sort speedup of the quantum adiabatic algorithm using delocalization catalysis
url http://doi.org/10.1103/PhysRevResearch.3.013092
work_keys_str_mv AT chenfengcao speedupofthequantumadiabaticalgorithmusingdelocalizationcatalysis
AT jianxue speedupofthequantumadiabaticalgorithmusingdelocalizationcatalysis
AT nicshannon speedupofthequantumadiabaticalgorithmusingdelocalizationcatalysis
AT robertjoynt speedupofthequantumadiabaticalgorithmusingdelocalizationcatalysis