Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum Systems

The simulation of many-body open quantum systems is key to solving numerous outstanding problems in physics, chemistry, material science, and in the development of quantum technologies. Near-term quantum computers may bring considerable advantage for the efficient simulation of their static and dyna...

Full description

Saved in:
Bibliographic Details
Main Authors: Sara Santos, Xinyu Song, Vincenzo Savona
Format: Article
Language:English
Published: Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften 2025-02-01
Series:Quantum
Online Access:https://quantum-journal.org/papers/q-2025-02-04-1620/pdf/
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832540651372150784
author Sara Santos
Xinyu Song
Vincenzo Savona
author_facet Sara Santos
Xinyu Song
Vincenzo Savona
author_sort Sara Santos
collection DOAJ
description The simulation of many-body open quantum systems is key to solving numerous outstanding problems in physics, chemistry, material science, and in the development of quantum technologies. Near-term quantum computers may bring considerable advantage for the efficient simulation of their static and dynamical properties, thanks to hybrid quantum-classical variational algorithms to approximate the dynamics of the density matrix describing the quantum state in terms of an ensemble average. Here, a variational quantum algorithm is developed to simulate the real-time evolution of the density matrix governed by the Lindblad master equation, under the assumption that the quantum state has a bounded entropy along the dynamics, entailing a low-rank representation of its density matrix. The algorithm encodes each pure state of the statistical mixture as a parametrized quantum circuit, and the associated probabilities as additional variational parameters stored classically, thereby requiring a significantly lower number of qubits than algorithms where the full density matrix is encoded in the quantum memory. Two variational ansatze are proposed, and their effectiveness is assessed in the simulation of the dynamics of a 2D dissipative transverse field Ising model. The results underscore the algorithm's efficiency in simulating the dynamics of open quantum systems in the low-rank regime with limited quantum resources on a near-term quantum device.
format Article
id doaj-art-2378736a985745cd8c092590955fe082
institution Kabale University
issn 2521-327X
language English
publishDate 2025-02-01
publisher Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften
record_format Article
series Quantum
spelling doaj-art-2378736a985745cd8c092590955fe0822025-02-04T16:32:24ZengVerein zur Förderung des Open Access Publizierens in den QuantenwissenschaftenQuantum2521-327X2025-02-019162010.22331/q-2025-02-04-162010.22331/q-2025-02-04-1620Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum SystemsSara SantosXinyu SongVincenzo SavonaThe simulation of many-body open quantum systems is key to solving numerous outstanding problems in physics, chemistry, material science, and in the development of quantum technologies. Near-term quantum computers may bring considerable advantage for the efficient simulation of their static and dynamical properties, thanks to hybrid quantum-classical variational algorithms to approximate the dynamics of the density matrix describing the quantum state in terms of an ensemble average. Here, a variational quantum algorithm is developed to simulate the real-time evolution of the density matrix governed by the Lindblad master equation, under the assumption that the quantum state has a bounded entropy along the dynamics, entailing a low-rank representation of its density matrix. The algorithm encodes each pure state of the statistical mixture as a parametrized quantum circuit, and the associated probabilities as additional variational parameters stored classically, thereby requiring a significantly lower number of qubits than algorithms where the full density matrix is encoded in the quantum memory. Two variational ansatze are proposed, and their effectiveness is assessed in the simulation of the dynamics of a 2D dissipative transverse field Ising model. The results underscore the algorithm's efficiency in simulating the dynamics of open quantum systems in the low-rank regime with limited quantum resources on a near-term quantum device.https://quantum-journal.org/papers/q-2025-02-04-1620/pdf/
spellingShingle Sara Santos
Xinyu Song
Vincenzo Savona
Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum Systems
Quantum
title Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum Systems
title_full Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum Systems
title_fullStr Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum Systems
title_full_unstemmed Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum Systems
title_short Low-Rank Variational Quantum Algorithm for the Dynamics of Open Quantum Systems
title_sort low rank variational quantum algorithm for the dynamics of open quantum systems
url https://quantum-journal.org/papers/q-2025-02-04-1620/pdf/
work_keys_str_mv AT sarasantos lowrankvariationalquantumalgorithmforthedynamicsofopenquantumsystems
AT xinyusong lowrankvariationalquantumalgorithmforthedynamicsofopenquantumsystems
AT vincenzosavona lowrankvariationalquantumalgorithmforthedynamicsofopenquantumsystems