Dressed atom revisited: Hamiltonian-independent treatment of the radiative cascade

Abstract

The dressed atom approach provides a tool to investigate the dynamics of an atom-laser system by fully retaining the quantum nature of the coherent mode. In its standard derivation, the internal atom-laser evolution is described within the rotating-wave approximation, which determines a doublet structure of the spectrum and the peculiar fluorescence triplet in the steady state. However, the rotating wave approximation may fail to apply to atomic systems subject to femtosecond light pulses, light-matter systems in the strong-coupling regime or sustaining permanent dipole moments. This work aims to demonstrate how the general features of the steady-state radiative cascade are affected by the interaction of the dressed atom with propagating radiation modes. Rather than focusing on a specific model, we analyze how these features depend on the parameters characterizing the dressed eigenstates in arbitrary atom-laser dynamics, given that a set of general hypotheses is satisfied. Our findings clarify the general conditions in which a description of the radiative cascade in terms of transition between dressed states is self-consistent. We provide a guideline to determine the properties of photon emission for any atom-laser interaction model, which can be particularly relevant when the model should be tailored to enhance a specific line. We apply the general results to the case in which a permanent dipole moment is a source of low-energy emission, whose frequency is of the order of the Rabi coupling.

arXiv comment13 pages, 4 figures

References in corpus (15)

• Circuit Quantum Electrodynamics: Coherent Coupling of a Single Photon to a Cooper Pair Box
• Beyond the Jaynes-Cummings model: circuit QED in the ultrastrong coupling regime
• On the Integrability of the Rabi Model
• Observation of the Bloch-Siegert Shift in a Qubit-Oscillator System in the Ultrastrong Coupling Regime
• Exact solvability of the quantum Rabi models within Bogoliubov operators
• The quantum Rabi model: solution and dynamics
• Photonic realization of the quantum Rabi model
• Matter Coupling to Strong Electromagnetic Fields in Two-Level Quantum Systems with Broken Inversion Symmetry
• Superconducting Phase Qubit Coupled to a Nanomechanical Resonator: Beyond the Rotating-Wave Approximation
• Cold-atom based implementation of the quantum Rabi model
• Asymmetric quantum dot in microcavity as a nonlinear optical element
• Creation of a squeezed photon distribution using artificial atoms with broken inversion symmetry
• Spontaneous emission in dispersive media without point-dipole approximation
• Unified approach to the nonlinear Rabi models
• Propagation of optically tunable coherent radiation in a gas of polar molecules