Generation of coherence in an exactly solvable nonlinear nanomechanical system

• URL: http://arxiv.org/abs/2008.08562v1
• Date: Wed, 19 Aug 2020 17:32:16 GMT
• Title: Generation of coherence in an exactly solvable nonlinear nanomechanical system
• Authors: A. K. Singh, L. Chotorlishvili, S. Srivastava, I. Tralle, Z. Toklikishvili, J. Berakdar and S. K. Mishra
• Abstract summary: This study is focused on the quantum dynamics of a nitrogen-vacancy center coupled to a nonlinear, periodically driven mechanical oscillator. We observe that the production of coherence through a unitary transformation depends on whether the system is prepared initially in mixed state. We prove that quantum chaos and diminishing of information about the mixed initial state favors the generation of quantum coherence through the unitary evolution.
• Score: 1.0775419935941009
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: This study is focused on the quantum dynamics of a nitrogen-vacancy (NV) center coupled to a nonlinear, periodically driven mechanical oscillator. For a continuous periodic driving that depends on the position of the oscillator, the mechanical motion is described by Mathieu elliptic functions. This solution is employed to study the dynamics of the quantum spin system including environmental effects and to evaluate the purity and the von Neumann entropy of the NV-spin. The unitary generation of coherence is addressed. We observe that the production of coherence through a unitary transformation depends on whether the system is prepared initially in mixed state. Production of coherence is efficient when the system initially is prepared in the region of the separatrix (i.e., the region where classical systems exhibit dynamical chaos). From the theory of dynamical chaos, we know that phase trajectories of the system passing through the homoclinic tangle have limited memory, and therefore the information about the initial conditions is lost. We proved that quantum chaos and diminishing of information about the mixed initial state favors the generation of quantum coherence through the unitary evolution. We introduced quantum distance from the homoclinic tangle and proved that for the initial states permitting efficient generation of coherence, this distance is minimal.

Related papers

• Liouvillian Dynamics of the Open Schwinger Model: String Breaking and Kinetic Dissipation in a Thermal Medium [0.0]
  We consider the string-breaking dynamics within the Schwinger model and investigate its modification inside a thermal medium. We analyze the Liouvillian gaps of a Lindblad equation and the time dependence of the system's von Neumann entropy. We discuss how the Liouvillian dynamics of the open Schwinger model can be simulated on quantum computers.
  arXiv  Detail & Related papers  (2023-08-07T19:15:55Z)
• Universality of critical dynamics with finite entanglement [68.8204255655161]
  We study how low-energy dynamics of quantum systems near criticality are modified by finite entanglement. Our result establishes the precise role played by entanglement in time-dependent critical phenomena.
  arXiv  Detail & Related papers  (2023-01-23T19:23:54Z)
• Geometric phases along quantum trajectories [58.720142291102135]
  We study the distribution function of geometric phases in monitored quantum systems. For the single trajectory exhibiting no quantum jumps, a topological transition in the phase acquired after a cycle. For the same parameters, the density matrix does not show any interference.
  arXiv  Detail & Related papers  (2023-01-10T22:05:18Z)
• Quantum Lyapunov exponent in dissipative systems [68.8204255655161]
  The out-of-time order correlator (OTOC) has been widely studied in closed quantum systems. We study the interplay between these two processes. The OTOC decay rate is closely related to the classical Lyapunov.
  arXiv  Detail & Related papers  (2022-11-11T17:06:45Z)
• Accelerating the approach of dissipative quantum spin systems towards stationarity through global spin rotations [0.0]
  We consider open quantum systems governed by a time-independent Markovian Lindblad Master equation. Such systems approach their stationary state on a timescale that is determined by the spectral gap of the generator of the Master equation dynamics. We show that even far simpler transformations constructed by a global unitary spin rotation allow to exponentially speed up relaxation.
  arXiv  Detail & Related papers  (2022-04-11T18:00:34Z)
• Unification of Random Dynamical Decoupling and the Quantum Zeno Effect [68.8204255655161]
  We show that the system dynamics under random dynamical decoupling converges to a unitary with a decoupling error that characteristically depends on the convergence speed of the Zeno limit. This reveals a unification of the random dynamical decoupling and the quantum Zeno effect.
  arXiv  Detail & Related papers  (2021-12-08T11:41:38Z)
• From geometry to coherent dissipative dynamics in quantum mechanics [68.8204255655161]
  We work out the case of finite-level systems, for which it is shown by means of the corresponding contact master equation. We describe quantum decays in a 2-level system as coherent and continuous processes.
  arXiv  Detail & Related papers  (2021-07-29T18:27:38Z)
• Breakdown of quantum-classical correspondence and dynamical generation of entanglement [6.167267225728292]
  We study the generation of quantum entanglement induced by an ideal Fermi gas confined in a chaotic cavity. We find that the breakdown of the quantum-classical correspondence of particle motion, via dramatically changing the spatial structure of many-body wavefunction, leads to profound changes of the entanglement structure.
  arXiv  Detail & Related papers  (2021-04-14T03:09:24Z)
• Sensing quantum chaos through the non-unitary geometric phase [62.997667081978825]
  We propose a decoherent mechanism for sensing quantum chaos. The chaotic nature of a many-body quantum system is sensed by studying the implications that the system produces in the long-time dynamics of a probe coupled to it.
  arXiv  Detail & Related papers  (2021-04-13T17:24:08Z)
• Exponentially accelerated approach to stationarity in Markovian open quantum systems through the Mpemba effect [0.0]
  We show that the relaxation dynamics of Markovian open quantum systems can be accelerated exponentially by devising an optimal unitary transformation. This initial "rotation" is engineered in such a way that the state of the quantum system becomes to the slowest decaying dynamical mode. We illustrate our idea by showing how to achieve an exponential speed-up in the convergence to stationarity in Dicke models.
  arXiv  Detail & Related papers  (2021-03-08T19:02:31Z)
• Quantum mold casting for topological insulating and edge states [0.0]
  We study the possibility of transferring fermions from a trivial system as particle source to an empty system. We show that this can be realized by a non-Hermitian unidirectional hopping. Our finding reveals a classical analogy of quench dynamics in quantum matter.
  arXiv  Detail & Related papers  (2021-01-03T10:02:48Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.