Cavity elimination in cavity-QED: a self-consistent input-output approach

• URL: http://arxiv.org/abs/2603.15508v1
• Date: Mon, 16 Mar 2026 16:37:17 GMT
• Title: Cavity elimination in cavity-QED: a self-consistent input-output approach
• Abstract summary: We introduce a self-consistent approach to eliminate the cavity degrees of freedom of cavity quantum electrodynamics.<n>We compute two-time correlations and spectral densities, showing an excellent agreement with full cavity quantum electrodynamics simulations.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Simplifying composite open quantum systems through model reduction is central to enable their analytical and numerical understanding. In this work, we introduce a self-consistent approach to eliminate the cavity degrees of freedom of cavity quantum electrodynamics (CQED) devices in the non-adiabatic regime, where the cavity memory time is comparable with the timescales of the atom dynamics. To do so, we consider a CQED system consisting of a two-level atom coupled to a single-mode cavity, both subsystems interacting with the environment through an arbitrary number of ports, within the input-output formalism. A self-consistency equation is derived for the reduced atom dynamics. This allows retrieving an exact expression for the effective Purcell-enhanced emission rate and, under reasonable approximations, a set of self-consistent dynamical equations and input-output relations for the effective two level atom. The resulting reduced model captures non-Markovian features, characterized through an effective Lindblad equation exhibiting two decoherence rates, a positive and a negative one. In the continuous-wave excitation regime, we benchmark our approach by computing effective steady states and output flux expressions beyond the low-power excitation regime, for which a semi-classical treatment is usually applied. We also compute two-time correlations and spectral densities, showing an excellent agreement with full cavity quantum electrodynamics simulations, except in the strong-coupling, high-excitation regime. Our results provide a practical framework for reducing the size of CQED models, which could be generalized to more complex atom and cavity configurations.

Related papers

• Generation and Enhancement of Bipartite and Tripartite Entanglement in an Electro-Optomechanical Ring Cavity [0.0]
  We investigate the generation and enhancement of quantum entanglement in an electro-optomechanical ring cavity system.<n>We find that the strength of entanglement is highly sensitive to several parameters and can be optimized through the strategic selection of the OPA's gain and phase.<n>These findings highlight the potential of such hybrid systems as versatile platforms for controlling multipartite entanglement in quantum technologies.
  arXiv  Detail & Related papers  (2026-08-04T12:33:45Z)
• Mean-field and fluctuation dynamics in off-resonant two-mode atom-field interactions [39.146761527401424]
  We study a two-level system coupled to two quantized electromagnetic modes within the Jaynes-Cummings framework.<n>While the single-mode model is exactly solvable due to its conserved excitation number, the two-mode model extension presents a fundamental challenge.<n>Our scheme separates the dynamics into a dominant, exactly solvable semiclassical component, the atom interacting with the mean fields of both modes.
  arXiv  Detail & Related papers  (2026-05-19T22:30:51Z)
• Comparison of the standard and dressed-picture master equations for the quantum Rabi model in the ultrastrong coupling regime [78.55450146498553]
  This chapter investigates the effects of relaxation and dephasing on the quantum Rabi model in the ultrastrong coupling regime.<n>It provides explicit formulas to implement and numerically solve the resulting nonunitary dynamics.
  arXiv  Detail & Related papers  (2026-04-10T01:22:07Z)
• Cavity magnomechanical framework for a high-efficiency quantum battery [0.23204268908909578]
  We investigate a quantum battery architecture where two identical two-level atoms are charged by a cavity-magnomechanical system.<n>We show that strong, resonant light-matter interactions are crucial for enhancing the key performance metrics.
  arXiv  Detail & Related papers  (2025-11-23T13:23:54Z)
• Renormalization and Low-Energy Effective Models in Cavity and Circuit QED [0.0]
  The quantum Rabi model (QRM) is a cornerstone in the study of light-matter interactions within cavity and circuit quantum electrodynamics.<n>We introduce a renormalized QRM that incorporates the effective influence of higher atomic energy levels.
  arXiv  Detail & Related papers  (2025-03-03T15:27:12Z)
• 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.<n>We find sufficient conditions under which dynamical decoupling works for such systems.<n>Our bounds reproduce the correct scaling in various relevant system parameters.
  arXiv  Detail & Related papers  (2024-09-24T04:58:28Z)
• Modeling Non-Covalent Interatomic Interactions on a Photonic Quantum Computer [50.24983453990065]
  We show that the cQDO model lends itself naturally to simulation on a photonic quantum computer. We calculate the binding energy curve of diatomic systems by leveraging Xanadu's Strawberry Fields photonics library. Remarkably, we find that two coupled bosonic QDOs exhibit a stable bond.
  arXiv  Detail & Related papers  (2023-06-14T14:44:12Z)
• Effective Hamiltonian approach to the exact dynamics of open system by complex discretization approximation for environment [0.0]
  We propose a generalization of the discretization approximation method into the complex frequency space basing on complex Gauss quadratures.<n>An effective Hamiltonian can be established by this way, which is non-Hermitian and demonstrates the complex energy modes with negative imaginary part.
  arXiv  Detail & Related papers  (2023-03-12T05:34:29Z)
• A Hybrid Quantum-Classical Method for Electron-Phonon Systems [40.80274768055247]
  We develop a hybrid quantum-classical algorithm suitable for this type of correlated systems. This hybrid method tackles with arbitrarily strong electron-phonon coupling without increasing the number of required qubits and quantum gates. We benchmark the new method by applying it to the paradigmatic Hubbard-Holstein model at half filling, and show that it correctly captures the competition between charge density wave and antiferromagnetic phases.
  arXiv  Detail & Related papers  (2023-02-20T08:08:51Z)
• Unconditional Wigner-negative mechanical entanglement with linear-and-quadratic optomechanical interactions [62.997667081978825]
  We propose two schemes for generating Wigner-negative entangled states unconditionally in mechanical resonators. We show analytically that both schemes stabilize a Wigner-negative entangled state that combines the entanglement of a two-mode squeezed vacuum with a cubic nonlinearity. We then perform extensive numerical simulations to test the robustness of Wigner-negative entanglement attained by approximate CPE states stabilized in the presence of thermal decoherence.
  arXiv  Detail & Related papers  (2023-02-07T19:00:08Z)
• On optimization of coherent and incoherent controls for two-level quantum systems [77.34726150561087]
  This article considers some control problems for closed and open two-level quantum systems. The closed system's dynamics is governed by the Schr"odinger equation with coherent control. The open system's dynamics is governed by the Gorini-Kossakowski-Sudarshan-Lindblad master equation.
  arXiv  Detail & Related papers  (2022-05-05T09:08:03Z)
• Lindblad master equations for quantum systems coupled to dissipative bosonic modes [0.0]
  We derive Lindblad master equations for a subsystem whose dynamics is coupled to bosonic modes. We apply this formalism to the dissipative Dicke model and derive a Lindblad master equation for the atomic spins. This master equation accurately predicts the Dicke phase transition and gives the correct steady state.
  arXiv  Detail & Related papers  (2022-03-07T11:21:48Z)
• Generalized Discrete Truncated Wigner Approximation for Nonadiabtic Quantum-Classical Dynamics [0.0]
  We introduce a linearized semiclassical method, the generalized discrete truncated Wigner approximation (GDTWA) GDTWA samples the electron degrees of freedom in a discrete phase space, and forbids an unphysical growth of electronic state populations. Our results suggest that the method can be very adequate to treat challenging nonadiabatic dynamics problems in chemistry and related fields.
  arXiv  Detail & Related papers  (2021-04-14T21:53:35Z)
• Assessment of weak-coupling approximations on a driven two-level system under dissipation [58.720142291102135]
  We study a driven qubit through the numerically exact and non-perturbative method known as the Liouville-von equation with dissipation. We propose a metric that may be used in experiments to map the regime of validity of the Lindblad equation in predicting the steady state of the driven qubit.
  arXiv  Detail & Related papers  (2020-11-11T22:45:57Z)

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.