Computing Quantum Mean Values in the Deep Chaotic Regime

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Lando, Gabriel M., Giraud, Olivier, Ullmo, Denis
Natura: Preprint
Pubblicazione: 2023
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866911934260969472
author Lando, Gabriel M.
Giraud, Olivier
Ullmo, Denis
author_facet Lando, Gabriel M.
Giraud, Olivier
Ullmo, Denis
contents We study the time evolution of mean values of quantum operators in a regime plagued by two difficulties: The smallness of $\hbar$ and the presence of strong and ubiquitous classical chaos. While numerics become too computationally expensive for purely quantum calculations as $\hbar \to 0$, methods that take advantage of the smallness of $\hbar$ -- that is, semiclassical methods -- suffer from both conceptual and practical difficulties in the deep chaotic regime. We implement an approach which addresses these conceptual problems, leading to a deeper understanding of the origin of the interference contributions to the operator's mean value. We show that in the deep chaotic regime our approach is capable of unprecedented accuracy, while a standard semiclassical method (the Herman-Kluk propagator) produces only numerical noise. Our work paves the way to the development and employment of more efficient and accurate methods for quantum simulations of systems with strongly chaotic classical limits.
format Preprint
id arxiv_https___arxiv_org_abs_2308_04655
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Computing Quantum Mean Values in the Deep Chaotic Regime
Lando, Gabriel M.
Giraud, Olivier
Ullmo, Denis
Quantum Physics
Chaotic Dynamics
We study the time evolution of mean values of quantum operators in a regime plagued by two difficulties: The smallness of $\hbar$ and the presence of strong and ubiquitous classical chaos. While numerics become too computationally expensive for purely quantum calculations as $\hbar \to 0$, methods that take advantage of the smallness of $\hbar$ -- that is, semiclassical methods -- suffer from both conceptual and practical difficulties in the deep chaotic regime. We implement an approach which addresses these conceptual problems, leading to a deeper understanding of the origin of the interference contributions to the operator's mean value. We show that in the deep chaotic regime our approach is capable of unprecedented accuracy, while a standard semiclassical method (the Herman-Kluk propagator) produces only numerical noise. Our work paves the way to the development and employment of more efficient and accurate methods for quantum simulations of systems with strongly chaotic classical limits.
title Computing Quantum Mean Values in the Deep Chaotic Regime
topic Quantum Physics
Chaotic Dynamics
url https://arxiv.org/abs/2308.04655