English
Related papers

Related papers: Computational complexity of non-equilibrium steady…

200 papers

This paper gives an overview of recent results concerning the long time dynamics of repeated interaction quantum systems in a deterministic and random framework. We describe the non equilibrium steady states (NESS) such systems display and…

Mathematical Physics · Physics 2017-08-23 Alain Joye

We investigate the phenomenon of spacetime-localized response in a quantum critical spin system, with particular attention to how it depends on the spatial profile and operator content of the applied perturbation, as well as its robustness…

Other Condensed Matter · Physics 2026-03-03 Daichi Imagawa , Keiju Murata , Daisuke Yamamoto

In this paper, the space complexity of nonuniform quantum computations is investigated. The model chosen for this are quantum branching programs, which provide a graphic description of sequential quantum algorithms. In the first part of the…

Quantum Physics · Physics 2007-05-23 M. Sauerhoff , D. Sieling

We present an application of autoregressive neural networks to Monte Carlo simulations of quantum spin chains using the correspondence with classical two-dimensional spin systems. We use a hierarchy of neural networks capable of estimating…

Quantum Physics · Physics 2026-05-19 Piotr Białas , Piotr Korcyl , Tomasz Stebel , Dawid Zapolski

We investigate signatures of quantum chaos within Ising spin chains subjected to transverse and longitudinal fields, incorporating both local (nearest-neighbor) and non-local (long-range) couplings. While local Ising models may exhibit…

We perform a mathematical analysis of the classical computational complexity of two genuine quantum-mechanical problems, which are inspired in the calculation of the expected magnetizations and the entanglement between subsystems for a…

Quantum Physics · Physics 2007-05-23 Roman Orus

We consider the identification of non-causal systems with arbitrary switching modes (NCS-ASM), a class of models essential for describing typical power load management and department store inventory dynamics. The simultaneous identification…

Information Theory · Computer Science 2024-09-06 Yanxin Zhang , Chengpu Yu , Filippo Fabiani

We develop in the weak coupling approximation a quasi-non-Markovian master equation and study the phenomenon of decoherence during the operation of a controlled-not (CNOT) quantum gate in a quantum computer model formed by a linear chain of…

Quantum Physics · Physics 2012-06-08 Pablo López , Gustavo López

We investigate how the computational difficulty of contracting tensor networks depends on the sign structure of the tensor entries. Using results from computational complexity, we observe that the approximate contraction of tensor networks…

Quantum Physics · Physics 2025-01-22 Jielun Chen , Jiaqing Jiang , Dominik Hangleiter , Norbert Schuch

We investigate the effect of a non-Markovian, structured reservoir on an open Heisenberg spin chain. We establish a coherent self-feedback mechanism as the reservoir couples frequency-dependent to the spin chain. Thus, loss and driving take…

Quantum Physics · Physics 2022-07-13 Regina Finsterhölzl , Manuel Katzer , Alexander Carmele

We study the computational complexity of simulating the time-dependent expectation value of a local operator in a one-dimensional quantum system by using temporal matrix product states. We argue that such cost is intimately related to that…

Statistical Mechanics · Physics 2024-07-08 Stefano Carignano , Carlos Ramos Marimón , Luca Tagliacozzo

This study investigates spin squeezed states in nuclear magnetic resonance (NMR) quadrupolar systems with spins $I=3/2$ and $I=7/2$ at room temperature, taking into account the effects of relaxation on the dynamics. The origin of spin…

The simulation of complex quantum systems on a quantum computer is studied, taking the kicked Harper model as an example. This well-studied system has a rich variety of dynamical behavior depending on parameters, displays interesting…

Quantum Physics · Physics 2007-05-23 Benjamin Levi , Bertrand Georgeot

In this paper we study one-dimensional quantum Ising spin chains in external magnetic field close to an integrable point. We concentrate on the dynamics of the slowest operator, that plays a key role at the final period of thermalization.…

Quantum Physics · Physics 2023-02-17 Ekaterina Izotova

A nonequilibrium statistical operator method is developed for ensembles of particles obeying non-Hamiltonian equations of motion in classical phase space. The main consequences of non-zero compressibility of phase space are examined in…

Statistical Mechanics · Physics 2007-05-23 Alexander V. Zhukov , Jianshu Cao

Closed quantum systems obey the Schroedinger equation whereas nonequilibrium behavior of many of systems is routinely described in terms of classical, Markovian stochastic processes. Evidently, there are fundamental differences between…

Quantum Physics · Physics 2016-02-29 Daniel Schmidtke , Jochen Gemmer

The numerical emulation of quantum systems often requires an exponential number of degrees of freedom which translates to a computational bottleneck. Methods of machine learning have been used in adjacent fields for effective feature…

Disordered Systems and Neural Networks · Physics 2020-08-10 A Berezutskii , M Beketov , D Yudin , Z Zimborás , J Biamonte

We review recent progress on constructing non-equilibrium steady state density operators of boundary driven locally interacting quantum chains, where driving is implemented via Markovian dissipation channels attached to the chain's ends. We…

Statistical Mechanics · Physics 2015-08-26 Tomaz Prosen

Simulating open quantum systems is essential for exploring novel quantum phenomena and evaluating noisy quantum circuits. In this Letter, we address the problem of whether mixed states generated from noisy quantum circuits can be…

Quantum Physics · Physics 2024-12-03 Yuchen Guo , Shuo Yang

Quantum many-body systems with kinetic constraints exhibit intriguing relaxation dynamics. Recent experimental progress in the field of cold atomic gases offers a handle for probing collective behavior of such systems, in particular for…

Quantum Gases · Physics 2019-06-12 Maike Ostmann , Matteo Marcuzzi , Juan P. Garrahan , Igor Lesanovsky