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We investigate the transition to quantum chaos, induced by static imperfections, for an operating quantum computer that simulates efficiently a dynamical quantum system, the sawtooth map. For the different dynamical regimes of the map, we…

Quantum Physics · Physics 2007-05-23 G. Benenti , G. Casati , S. Montangero , D. L. Shepelyansky

Towards better understanding of how to design efficient adiabatic quantum algorithms, we study how the adiabatic gap depends on the spectra of the initial and final Hamiltonians in a natural family of test-bed examples. We show that perhaps…

Mathematical Physics · Physics 2019-06-07 Yosi Atia , Dorit Aharonov

We propose a measure of quantum state complexity defined by minimizing the spread of the wave-function over all choices of basis. Our measure is controlled by the "survival amplitude" for a state to remain unchanged, and can be efficiently…

High Energy Physics - Theory · Physics 2022-09-14 Vijay Balasubramanian , Pawel Caputa , Javier Magan , Qingyue Wu

This work is concerned with determination of the steady-state structure of time-independent Lindblad master equations, especially those possessing more than one steady state. The approach here is to treat Lindblad systems as generalizations…

Quantum Physics · Physics 2014-02-24 Victor V. Albert , Liang Jiang

We study the entanglement dynamics of multi-qubit systems coupled to a common dissipative environment, focusing on systems with one or two initially excited qubits. Using the Lindblad master equation, we derive the time evolution of the…

Quantum Physics · Physics 2025-04-15 Z. Bakhshi , E. Morsheddoost , A. Zeynali

Quantum metrology protocols allow to surpass precision limits typical to classical statistics. However, in recent years, no-go theorems have been formulated, which state that typical forms of uncorrelated noise can constrain the quantum…

Quantum Physics · Physics 2016-03-30 Andrea Smirne , Jan Kolodynski , Susana F. Huelga , Rafal Demkowicz-Dobrzanski

A topological frequency converter represents a dynamical counterpart of the integer quantum Hall effect, where a two-level system enacts a quantized time-averaged power transfer between two driving modes of incommensurate frequency. Here,…

Mesoscale and Nanoscale Physics · Physics 2024-09-16 Florian Koch , Jan Carl Budich

We construct lower bounds to the spectral gap of a family of Lindblad generators known as Davies maps. These maps describe the thermalization of quantum systems weakly coupled to a heat bath. The steady state of these systems is given by…

Quantum Physics · Physics 2014-12-10 Kristan Temme

We introduce a framework for implementing quantum operations as steady states of a subsystem in an extended Hilbert space. Each operation has a spectral criterion for reaching the steady state. This adds a `spectral switch' mechanism to the…

Quantum Physics · Physics 2026-03-27 Man Yin Cheung , Mona Berciu , Kyle Monkman

In order to study the resonance spectra of chaotic cavities subject to some damping (which can be due to absorption or partial reflection at the boundaries), we use a model of damped quantum maps. In the high-frequency limit, the…

Chaotic Dynamics · Physics 2009-04-23 Stéphane Nonnenmacher , Emmanuel Schenck

The dynamical evolution of an open quantum system can be governed by the Lindblad equation of the density matrix. In this paper, we propose to characterize the density matrix topology by the topological invariant of its modular Hamiltonian.…

Mesoscale and Nanoscale Physics · Physics 2024-06-27 Liang Mao , Fan Yang , Hui Zhai

The presence of a dissipative environment disrupts the unitary spectrum of dynamical quantum maps. Nevertheless, key features of the underlying unitary dynamics -- such as their integrable or chaotic nature -- are not immediately erased by…

In the framework of the Lindblad theory for open quantum systems, expressions for the density operator, von Neumann entropy and effective temperature of the damped harmonic oscillator are obtained. The entropy for a state characterized by a…

Quantum Physics · Physics 2015-06-26 A. Isar

Master equations in the Lindblad form describe evolution of open quantum systems that is completely positive and simultaneously has a semigroup property. We analyze a possibility to derive this type of master equations from an intrinsically…

Quantum Physics · Physics 2007-05-23 Mario Ziman , Peter Stelmachovic , Vladimir Buzek

We show that noisy quantum dynamics exposed to weak measurements exhibit a spectral transition between gapless and gapped phases. To this end, we employ the Lyapunov spectrum obtained through singular values of a non-unitary matrix…

Quantum Physics · Physics 2025-01-10 Ken Mochizuki , Ryusuke Hamazaki

Markovian open many-body quantum systems display complicated relaxation dynamics. The spectral gap of the Liouvillian characterizes the asymptotic decay rate towards the stationary state, but it has recently been pointed out that the…

Statistical Mechanics · Physics 2024-07-30 Tatsuhiko Shirai , Takashi Mori

A quantum system subject to continuous measurement and post-selection evolves according to a non-Hermitian Hamiltonian. We show that, as one increases the rate of post-selection, this non-Hermitian Hamiltonian undergoes a spectral phase…

Quantum Physics · Physics 2021-05-04 Sarang Gopalakrishnan , Michael J. Gullans

We consider the dynamics of generic chaotic quantum many-body systems with no conservation laws, subject to weak bulk dissipation. It was recently observed [T. Mori, arXiv:2311.10304] that the generator of these dissipative dynamics, a…

Quantum Physics · Physics 2025-05-15 J. Alexander Jacoby , David A. Huse , Sarang Gopalakrishnan

The generic behavior of purely dissipative open quantum many-body systems with local dissipation processes can be investigated using random matrix theory, revealing a hierarchy of decay timescales of observables organized by their…

Quantum Physics · Physics 2024-02-12 Nick D. Hartmann , Jimin L. Li , David J. Luitz

We study relaxation times, also called mixing times, of quantum many-body systems described by a Lindblad master equation. We in particular study the scaling of the spectral gap with the system length, the so-called dynamical exponent,…

Statistical Mechanics · Physics 2015-10-30 Marko Znidaric