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Related papers: An instability of unitary quantum dynamics

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In this work we study the unitary time-evolutions of quantum systems defined on infinite-dimensional separable time-dependent Hilbert spaces. Two possible cases are considered: a quantum system defined on a stochastic interval and another…

Quantum Physics · Physics 2019-05-22 Luca Curcuraci , Stefano Bacchi , Angelo Bassi

We analyze the asymptotic dynamics of quantum systems resulting from large numbers of iterations of random unitary operations. Although, in general, these quantum operations cannot be diagonalized it is shown that their resulting asymptotic…

Quantum Physics · Physics 2018-02-14 J. Novotny , G. Alber , I. Jex

The temporal evolution of an unstable quantum mechanical system undergoing repeated measurements is investigated. In general, by changing the time interval between successive measurements, the decay can be accelerated (inverse quantum Zeno…

Quantum Physics · Physics 2009-11-06 P. Facchi , H. Nakazato , S. Pascazio

The dynamical equation satisfied by the density matrix, when a quantum system is subjected to one or more constraints arising from conserved quantities, is derived. The resulting nonlinear motion of the density matrix has the property that…

Quantum Physics · Physics 2015-02-23 Dorje C. Brody , Anna C. T. Gustavsson , Lane P. Hughston

We study the quantum dynamics generated by the repeated action of a non-unitary evolution operator on a system of qubits. Breaking unitarity can lead to the purification of mixed initial states, which corresponds to the loss of sensitivity…

Quantum Physics · Physics 2025-12-03 Yi-Cheng Wang , Ehud Altman , Samuel J. Garratt

We consolidate coherence, athermality, and nonuniformity as sub-resources within an underlying quantum resource theory: instability. We formulate instability axiomatically as the transient information within a decaying physical system.…

Quantum Physics · Physics 2026-02-23 Goni Yoeli , Gilad Gour

The underlying mechanism in the implementation of unitary operation on a system with an external apparatus is studied. We implement the unitary time evolution in the system as a physical phenomenon that results from the interaction between…

Quantum Physics · Physics 2018-09-17 Hiroyasu Tajima , Naoto Shiraishi , Keiji Saito

It is shown that a periodic perturbation of the quantum pendulum (similarly to the classical one) in the neighbourhood of the separatrix can bring about irreversible phenomena. As a result of recurrent passages between degenerate states,…

Chaotic Dynamics · Physics 2007-05-23 A. Ugulava , L. Chotorlishvili , K. Nickoladze

This paper considers uncertainty quantification in systems perturbed by stochastic disturbances, in particular, Gaussian white noise. The main focus of this work is on describing the time evolution of statistical moments of certain…

Systems and Control · Electrical Eng. & Systems 2020-07-28 Anant A. Joshi , Kamesh Subbarao

The thermodynamics of quantum systems driven out of equilibrium has attracted increasing attention in last the decade, in connection with quantum information and statistical physics, and with a focus on non-classical signatures. While a…

Quantum Physics · Physics 2022-06-01 Gonzalo Manzano , Roberta Zambrini

Phase transitions not allowed in equilibrium steady states may happen however at the fluctuating level. We observe for the first time this striking and general phenomenon measuring current fluctuations in an isolated diffusive system. While…

Statistical Mechanics · Physics 2011-10-31 Pablo I. Hurtado , Pedro L. Garrido

We study the dynamics of a two-level quantum system interacting with an external electromagnetic field periodic and quasiperiodic in time. The quantum evolution is described exactly by the classical equations of motion of a gyromagnet in a…

Quantum Physics · Physics 2009-11-11 Renato M. Angelo , Walter F. Wreszinski

Classical optomechanical systems feature self-sustained oscillations, where multiple periodic orbits at different amplitudes coexist. We study how this multistability is realized in the quantum regime, where new dynamical patterns appear…

Quantum Physics · Physics 2016-04-19 C. Schulz , A. Alvermann , L. Bakemeier , H. Fehske

We discuss the intimate connection between the chaotic dynamics of a classical field theory and the instability of the one-loop effective action of the associated quantum field theory. Using the example of massless scalar electrodynamics,…

High Energy Physics - Theory · Physics 2009-10-30 Sergei G. Matinyan , Berndt Müller

We study the dynamics of a "kicked" quantum system undergoing repeated measurements of momentum. A diffusive behavior is obtained for a large class of Hamiltonians, even when the dynamics of the classical counterpart is not chaotic. These…

Quantum Physics · Physics 2007-05-23 P. Facchi , S. Pascazio , A. Scardicchio

We show that introducing a small uncertainty in the parameters of quantum systems can make the dynamics of these systems robust against perturbations. Concretely, for the case where a system is subject to perturbations due to an…

Quantum Physics · Physics 2017-11-22 Meenu Kumari , Eduardo Martin-Martinez , Achim Kempf , Shohini Ghose

Many measurements on soft condensed matter (e.g., biological and materials) systems track low-dimensional observables projected from the full system phase space as a function of time. Examples are dynamic structure factors, spectroscopic…

Statistical Mechanics · Physics 2021-02-03 Alessio Lapolla , Jeremy C. Smith , Aljaž Godec

The superposition of causal order shows promise in various quantum technologies. However, the fragility of quantum systems arising from environmental interactions, leading to dissipative behavior and irreversibility, demands a deeper…

A large number of multifaceted quantum transport processes in molecular systems and physical nanosystems can be treated in terms of quantum relaxation processes which couple to one or several fluctuating environments. A thermal equilibrium…

Statistical Mechanics · Physics 2007-05-23 Igor Goychuk , Peter Hanggi

We study the dynamics of a quantum system having Hilbert space of finite dimension $d_{\mathrm{H}}$. Instabilities are possible provided that the master equation governing the system's dynamics contain nonlinear terms. Here we consider the…

Quantum Physics · Physics 2021-06-02 Eyal Buks , Dvir Schwartz