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Time evolution of quantum systems is accelerated by the fast-forward scaling. We reformulate the method to study systems in a finite-dimensional Hilbert space. For several simple systems, we explicitly construct the acceleration potential.…

Quantum Physics · Physics 2014-04-24 Kazutaka Takahashi

Dissipative systems with decoherence free subspaces, a.k.a. dark spaces (DSs), can be used to protect quantum information. At the same time, dissipation is expected to give rise to coherent information degradation outside the DS. Employed…

Quantum Physics · Physics 2025-05-29 Raul A. Santos , Alex Kamenev , Yuval Gefen

Symmetry-breaking transitions are a well-understood phenomenon of closed quantum systems in quantum optics, condensed matter, and high energy physics. However, symmetry breaking in open systems is less thoroughly understood, in part due to…

We consider an ensemble of quantum systems whose average evolution is described by a density matrix, solution of a Lindblad-Kossakowski differential equation. We focus on the special case where the decoherence is only due to a highly…

Mathematical Physics · Physics 2008-01-11 Mazyar Mirrahimi , Pierre Rouchon

A potential problem with adiabatic switching in perturbation theory is that divergent terms appear in the series solution. An example of this was presented by C. Brouder et al [4] for a simple 2 state system where the evolution of system in…

Quantum Physics · Physics 2016-08-31 Dan Solomon

We consider a periodically driven system where the high-frequency driving protocol consists of a sequence of potentials switched on and off at different instants within a period. We explore the possibility of introducing an adiabatic…

Quantum Physics · Physics 2025-02-26 Ashwin Murali , Tapomoy Guha Sarkar , Jayendra N. Bandyopadhyay

Complete positivity of quantum dynamics is often viewed as a litmus test for physicality, yet it is well known that correlated initial states need not give rise to completely positive evolutions. This observation spurred numerous…

Quantum Physics · Physics 2016-02-22 Jason M. Dominy , Alireza Shabani , Daniel A. Lidar

Big Data is characterized by Volume, Velocity, Veracity and Complexity. The interaction between this huge data is complex with an associated free will having dynamic and non linear nature. We reduced big data based on its characteristics,…

Other Computer Science · Computer Science 2018-05-30 Sahil Imtiyaz

We consider the time evolution of the density matrix $\rho$ in a 2-dimensional complex Hilbert space. We allow for dissipation by adding to the von Neumann equation a term $D[\rho]$, which is of Lindblad type in order to assure complete…

Quantum Physics · Physics 2009-11-07 R. A. Bertlmann , W. Grimus

A completely positive master equation describing quantum dissipation for a Brownian particle is derived starting from microphysical collisions, exploiting a recently introduced approach to subdynamics of a macrosystem. The obtained equation…

Quantum Physics · Physics 2009-11-06 B. Vacchini

The state of an open quantum system undergoing an adiabatic process evolves by following the instantaneous stationary state of its time-dependent generator. This observation allows one to characterize, for a generic adiabatic evolution, the…

Statistical Mechanics · Physics 2024-01-23 Paulo J. Paulino , Igor Lesanovsky , Federico Carollo

We decompose the quantum adiabatic evolution as the products of gauge invariant unitary operators and obtain the exact nonadiabatic correction in the adiabatic approximation. A necessary and sufficient condition that leads to adiabatic…

Quantum Physics · Physics 2016-05-12 Zhen-Yu Wang , Martin B. Plenio

We determine the incoherent spectrum, squeezing properties and second-order correlation function of the collective atomic degrees of freedom in absorptive optical bistability. This is accomplished via a linearized Fokker-Planck equation in…

Quantum Physics · Physics 2020-11-09 Th. K. Mavrogordatos

Let the adiabatic invariant of action variable in slow-fast Hamiltonian system with two degrees of freedom have two limiting values along the trajectories as time tends to infinity. The difference of two limits is exponentially small in…

Dynamical Systems · Mathematics 2015-05-27 Tan Su

The method of adiabatic elimination has been widely adopted in quantum optics in the past several decades. In the study of cavity-based light-matter interactions, the bad-cavity limit is often encountered, where the damping rate of the…

Quantum Physics · Physics 2024-11-19 Hong Xie , Le-Wei He , Xiu-Min Lin

It is generally believed that a generic system can be reversibly transformed from one state into another by sufficiently slow change of parameters. A standard argument favoring this assertion is based on a possibility to expand the energy…

Statistical Mechanics · Physics 2008-11-26 Anatoli Polkovnikov , Vladimir Gritsev

Under sufficiently slow driving, thermodynamics predicts reversible evolution through a sequence of equilibrium states. We show that this expectation fails near spectral degeneracy in driven quadratic Hamiltonian systems. As the soft-mode…

Statistical Mechanics · Physics 2026-04-14 Ilki Kim

The reduced dynamics of an open quantum system obtained from an underlying microscopic Hamiltonian can in general only approximately be described by a time local master equation. The quality of that approximation depends primarily on the…

Quantum Physics · Physics 2020-01-15 Richard Hartmann , Walter T. Strunz

We study superadiabatic quantum control of a three-level quantum system whose energy spectrum exhibits multiple avoided crossings. In particular, we investigate the possibility of treating the full control task in terms of independent…

Quantum Physics · Physics 2017-08-02 Marcus Theisen , Francesco Petiziol , Stefano Carretta , Paolo Santini , Sandro Wimberger

The adiabatic theorem is a fundamental result established in the early days of quantum mechanics, which states that a system can be kept arbitrarily close to the instantaneous ground state of its Hamiltonian if the latter varies in time…

Quantum Gases · Physics 2022-06-01 Oleg Lychkovskiy , Oleksandr Gamayun , Vadim Cheianov