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Related papers: Decoherence and the Loschmidt echo

200 papers

Integrable non-linear Hamiltonian systems perturbed by additive noise develop a Lyapunov instability, and are hence chaotic, for any amplitude of the perturbation. This phenomenon is related, but distinct, from Taylor's diffusion in…

Chaotic Dynamics · Physics 2014-01-03 Khanh-Dang Nguyen Thu Lam , Jorge Kurchan

Recent work has connected the type of fidelity decay in perturbed quantum models to the presence of chaos in the associated classical models. We demonstrate that a system's rate of fidelity decay under repeated perturbations may be measured…

Quantum Physics · Physics 2009-11-07 Joseph Emerson , Yaakov S. Weinstein , Seth Lloyd , D. G. Cory

The interaction between solid-state qubits and their environmental degrees of freedom produces non-unitary effects like decoherence and dissipation. Uncontrolled decoherence is one of the main obstacles that must be overcome in quantum…

Quantum Physics · Physics 2014-11-24 Paula I. Villar , Fernando C. Lombardo

We show via an explicit example that quantum anomalies can lead to decoherence of a single quantum qubit through phase relaxation. The anomaly causes the Hamiltonian to develop a non-self-adjoint piece due to the non-invariance of the…

Quantum Physics · Physics 2011-11-10 W. F. Chen , R. Kobes , G. Kunstatter

We study the temporal evolution of a central spin-1/2 (qubit) coupled to the environment which is chosen to be a spin-1/2 transverse XY spin chain. We explore the entire phase diagram of the spin-Hamiltonian and investigate the behavior of…

Statistical Mechanics · Physics 2015-06-04 Shraddha Sharma , Victor Mukherjee , Amit Dutta

The diverging responses to parameter variations of systems at quantum critical points motivate schemes of quantum metrology that feature sub-Heisenberg scaling of the sensitivity with the system size (e.g., the number of particles). This…

Quantum Physics · Physics 2021-08-11 Chong Chen , Ping Wang , Ren-Bao Liu

We consider environment induced decoherence of quantum superpositions to mixtures in the limit in which that process is much faster than any competing one generated by the Hamiltonian $H_{\rm sys}$ of the isolated system. This interaction…

Quantum Physics · Physics 2007-05-23 Walter T. Strunz , Fritz Haake , Daniel Braun

Complexity in strongly correlated electron systems is analyzed by considering decoherence process between the localized state, |L> and the itinerant state, |I>. The coherent superposition state of a|I> + b|L> decoheres to the pointer states…

Strongly Correlated Electrons · Physics 2011-01-04 Byung Gyu Chae

The conventional conception of decoherence relies on the interaction with an external set of degrees of freedom - the 'bath' - to which the system loses quantum information. But the role of the bath can be played too by any internal degrees…

Quantum Gases · Physics 2019-09-20 L. Rico-Pérez

The interaction of a particle with vacuum fluctuations--which theoretically exist even in the complete absence of matter--can lead to observable irreversible decoherence if it were possible to switch on and off the particle charge suddenly.…

Quantum Physics · Physics 2025-07-10 Anirudh Gundhi , Hendrik Ulbricht

Effect of noise in inducing order on various chaotically evolving systems is reviewed, with special emphasis on systems consisting of coupled chaotic elements. In many situations it is observed that the uncoupled elements when driven by…

chao-dyn · Physics 2015-06-24 Manojit Roy , R. E. Amritkar

The stability of quantum systems to perturbations of the Hamiltonian is studied. This stability is quantified by the fidelity. Dependence of fidelity on the initial state as well as on the dynamical properties of the system is considered.…

Quantum Physics · Physics 2007-05-23 Marko Znidaric

One of the fundamental manifestations of classical chaos is exponential sensitivity to initial conditions that is, two trajectories starting from nearly identical initial states diverge exponentially over time. This behavior is quantified…

Quantum Physics · Physics 2026-04-16 Ignacio García-Mata , Diego A. Wisniacki

We study the intrinsic, disorder-induced decoherence of an isolated quantum system under its own dynamics. Specifically, we investigate the characteristic time scale (i.e., the decoherence time) associated with an interacting many-body…

Disordered Systems and Neural Networks · Physics 2017-01-11 Yang-Le Wu , Dong-Ling Deng , Xiaopeng Li , S. Das Sarma

We study the effects of dissipation and decoherence induced on a harmonic oscillator by the coupling to a chaotic system with two degrees of freedom. Using the Feynman-Vernon approach and treating the chaotic system semiclassically we show…

Quantum Physics · Physics 2009-11-13 M. V. S. Bonanca , M. A. M. de Aguiar

Using the Standard Map model, this study explores the quantum Loschmidt Echo (LE) decay laws for mixed-type phase spaces, including edge of chaos and chaotic sea regimes. A universal decay law is proposed and numerically verified,…

Quantum Physics · Physics 2025-01-06 Wenjun Shi

We investigate the nonequilibrium dynamics and loss of coherence in a quantum impurity system using the spinless resonant level model subject to sudden quenches of the hybridization between the impurity and the metal. The survival…

Mesoscale and Nanoscale Physics · Physics 2026-05-05 Felipe D. Picoli , Gustavo Diniz , Luiz N. Oliveira

We consider the description of quantum noise within the framework of the standard Copenhagen interpretation of quantum mechanics applied to a composite system environment setting. Averaging over the environmental degrees of freedom leads to…

Quantum Physics · Physics 2016-11-04 Bassano Vacchini

Decoherence of quantum bits arises primarily from the parasitic resistance within the qubit. This study presents the analysis of the decoherence process due to physical interactions between the qubit photons and parasitic resistance atoms,…

Quantum Physics · Physics 2025-10-30 Yoav Koral , Shilo Avraham , Manimuthu Peryasamy , Shmuel E. Schacham , Eliyahu Farber

Quantum chaos, a phenomenon that began to be studied in the last century, still does not have a rigorous understanding. By virtue of the correspondence principle, the properties of the system that lead to chaotic dynamics at the classical…

Quantum Physics · Physics 2024-06-25 Evgeny Polyakov , Nataliya Arefyeva