An exact Markovian decoherence dynamics of two interacting harmonic oscillators coupled to a bosonic heat bath

• URL: http://arxiv.org/abs/2507.01605v1
• Date: Wed, 02 Jul 2025 11:13:26 GMT
• Title: An exact Markovian decoherence dynamics of two interacting harmonic oscillators coupled to a bosonic heat bath
• Authors: Gábor Homa, Dávid Hamar, József Zsolt Bernád, Peter Adam, András Csordás,
• Abstract summary: We present an exact analytical solution of the Hu-Paz-Zhang master equation in a precise Markovian limit for a system of two harmonically coupled harmonic oscillators.<n>The thermal bath is initially considered to be at arbitrary temperatures and characterized by an Ohmic Lorentz-Drude spectral density.<n>We show that for negative values of the direct coupling between the oscillators, which are sufficiently close to a critical lower bound beyond which the system becomes unstable, the system can maintain entanglement across a broad temperature range and for arbitrarily long durations.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We present an exact analytical solution of the Hu-Paz-Zhang master equation in a precise Markovian limit for a system of two harmonically coupled harmonic oscillators interacting with a common thermal bath of harmonic oscillators. The thermal bath is initially considered to be at arbitrary temperatures and characterized by an Ohmic Lorentz-Drude spectral density. In the examined system, couplings between the two harmonic oscillators and the environment ensure a complete decoupling of the center-of-mass and relative degrees of freedom, resulting in undamped dynamics in the relative coordinate. The exact time evolution is used to analyze the system's entanglement dynamics, quantified through logarithmic negativity and quantum mutual information, while ensuring the positivity of the density operator to confirm the physical validity of the results. We demonstrate that, under certain parameter regimes and initial conditions, the asymptotic dynamics can give rise to periodic entanglement-disentanglement behavior. Furthermore, numerical simulations reveal that for negative values of the direct coupling between the oscillators, which are sufficiently close to a critical lower bound beyond which the system becomes unstable, the system can maintain entanglement across a broad temperature range and for arbitrarily long durations.

Related papers

• An open harmonic chain: Exact vs global and local reduced dynamics [0.0]
  We derive the steady states of the open chain quantum dynamics in two approaches.<n>We show the existence of a temperature-dependent critical inter-oscillator coupling strength that determines the domain of validity of each approach.
  arXiv  Detail & Related papers  (2025-05-22T13:33:00Z)
• Equilibrium and nonequilibrium steady states with the repeated interaction protocol: Relaxation dynamics and energetic cost [44.99833362998488]
  We study the dynamics of a qubit system interacting with thermalized bath-ancilla spins via a repeated interaction scheme.<n>Our key finding is that deterministic system-ancilla interactions do not typically result in the system thermalizing to the thermal state of the ancilla.
  arXiv  Detail & Related papers  (2025-01-09T17:35:36Z)
• Measurement-induced transitions for interacting fermions [43.04146484262759]
  We develop a field-theoretical framework that provides a unified approach to observables characterizing entanglement and charge fluctuations.<n>Within this framework, we derive a replicated Keldysh non-linear sigma model (NLSM)<n>By using the renormalization-group approach for the NLSM, we determine the phase diagram and the scaling of physical observables.
  arXiv  Detail & Related papers  (2024-10-09T18:00:08Z)
• Efficiency of Dynamical Decoupling for (Almost) Any Spin-Boson Model [44.99833362998488]
  We analytically study the dynamical decoupling of a two-level system coupled with a structured bosonic environment. We find sufficient conditions under which dynamical decoupling works for such systems. Our bounds reproduce the correct scaling in various relevant system parameters.
  arXiv  Detail & Related papers  (2024-09-24T04:58:28Z)
• Bounding the rotating wave approximation for coupled harmonic oscillators [34.82692226532414]
  We study the validity of the rotating wave approximation of an ideal system composed of two harmonic oscillators evolving with a quadratic Hamiltonian and arbitrarily strong interaction.<n>We are able to fully quantify the deviation of arbitrary pure Gaussian states that evolve through different dynamics from a common quantum state.
  arXiv  Detail & Related papers  (2024-03-22T16:51:53Z)
• Nonequilibrium quantum heat transport between structured environments [0.0]
  We apply the hierarchical equations of motion technique to analyze nonequilibrium heat transport in a spin-boson type model. We find the heat current to be drastically modified at weak system-bath coupling. Our analysis highlights a novel mechanism for controlling heat transport in nanoscale systems.
  arXiv  Detail & Related papers  (2024-03-20T18:20:12Z)
• Stochastic action for the entanglement of a noisy monitored two-qubit system [55.2480439325792]
  We study the effect of local unitary noise on the entanglement evolution of a two-qubit system subject to local monitoring and inter-qubit coupling. We construct a Hamiltonian by incorporating the noise into the Chantasri-Dressel-Jordan path integral and use it to identify the optimal entanglement dynamics. Numerical investigation of long-time steady-state entanglement reveals a non-monotonic relationship between concurrence and noise strength.
  arXiv  Detail & Related papers  (2024-03-13T11:14:10Z)
• Mixing thermal coherent states for precision and range enhancement in quantum thermometry [0.0]
  We propose the realization of a special mixture of thermal coherent states by coupling a thermal bath with a two-level system that is longitudinally coupled to a resonator.<n>We find that the state of the resonator is a special mixture of two oppositely displaced thermal coherent states, whereas the two-level system remains thermal.<n>In this context, the resonator functions as a probe to measure the unknown temperature of a bath mediated by a two-level system.
  arXiv  Detail & Related papers  (2023-06-07T12:04:55Z)
• Slow semiclassical dynamics of a two-dimensional Hubbard model in disorder-free potentials [77.34726150561087]
  We show that introduction of harmonic and spin-dependent linear potentials sufficiently validates fTWA for longer times. In particular, we focus on a finite two-dimensional system and show that at intermediate linear potential strength, the addition of a harmonic potential and spin dependence of the tilt, results in subdiffusive dynamics.
  arXiv  Detail & Related papers  (2022-10-03T16:51:25Z)
• Photoinduced prethermal order parameter dynamics in the two-dimensional large-$N$ Hubbard-Heisenberg model [77.34726150561087]
  We study the microscopic dynamics of competing ordered phases in a two-dimensional correlated electron model. We simulate the light-induced transition between two competing phases.
  arXiv  Detail & Related papers  (2022-05-13T13:13:31Z)
• Quantum approach to the thermalization of the toppling pencil interacting with a finite bath [0.0]
  We investigate the longstanding problem of thermalization of quantum systems coupled to an environment. The long-time average of the double-well energy is found to be a monotonously decaying function.
  arXiv  Detail & Related papers  (2021-11-19T12:30:34Z)
• Harmonic chains and the thermal diode effect [0.0]
  We prove that perfectly harmonic junctions can rectify heat once the reservoirs are placed under temperature gradients. Our study shows that asymmetric harmonic systems, such as room-temperature hydrocarbon molecules with varying side groups, or a linear lattice of trapped ions may rectify heat by going beyond simple boundary conditions.
  arXiv  Detail & Related papers  (2021-02-26T20:39:58Z)

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.