Quantum Phase Diagrams of Matter-Field Hamiltonians II: Wigner Function Analysis

Abstract

Non-classical states are of practical interest in quantum computing and quantum metrology. These states can be detected through their Wigner function negativity in some regions. In this paper, we calculate the ground state of the three-level generalised Dicke model for a single atom and determine the structure of its phase diagram using a fidelity criterion. We also calculate the Wigner function of the electromagnetic modes of the ground state through the corresponding reduced density matrix, and show in the phase diagram the regions where entanglement is present. A finer classification for the continuous phase transitions is obtained through the computation of the surface of maximum Bures distance.

arXiv comment22 pages, 11 figures

References in corpus (6)

• Negativity of the Wigner function as an indicator of nonclassicality
• Direct measurement of the Wigner function by photon counting
• Semi-classical and quantum Rabi models: in celebration of 80 years
• Quantum phase space measurement and entanglement validation made easy
• Polychromatic phase diagram for $n$-level atoms interacting with $\ell$ modes of electromagnetic field
• Optimal basis for the generalized Dicke model

Cited by in corpus (6)

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• Geometry, quantum correlations, and phase transitions in the $\Lambda$-atomic configuration
• Effect of the Atomic Dipole-Dipole Interaction on the Phase Diagrams of Field-Matter Interactions I: Variational procedure