Thermalization of coupled atom-light states in the presence of optical collisions

Abstract

The interaction of a two-level atomic ensemble with a quantized single mode electromagnetic field in the presence of optical collisions (OC) is investigated both theoretically and experimentally. The main accent is made on achieving thermal equilibrium for coupled atom-light states (in particular dressed states). We propose a model of atomic dressed state thermalization that accounts for the evolution of the pseudo-spin Bloch vector components and characterize the essential role of the spontaneous emission rate in the thermalization process. Our model shows that the time of thermalization of the coupled atom-light states strictly depends on the ratio of the detuning and the resonant Rabi frequency. The predicted time of thermalization is in the nanosecond domain and about ten times shorter than the natural lifetime at full optical power in our experiment. Experimentally we are investigating the interaction of the optical field with rubidium atoms in an ultra-high pressure buffer gas cell under the condition of large atom-field detuning comparable to the thermal energy in frequency units. In particular, an observed detuning dependence of the saturated lineshape is interpreted as evidence for thermal equilibrium of coupled atom-light states. A significant modification of sideband intensity weights is predicted and obtained in this case as well.

14 pages, 12 figures; the content was edited

References in corpus (9)

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Cited by in corpus (6)

• Nonlinear properties and stabilities of polaritonic crystals beyond the low-excitation-density limit
• High temperature phase transition in the coupled atom-light system in the presence of optical collisions
• One-dimensional Bose-Einstein condensation of photons in a microtube
• Lasing and high temperature phase transitions in atomic systems with dressed state polaritons
• Light Confinement by a Cylindric Metallic Waveguide in Dense Buffer Gas Environment
• Laser Cooling of Dense Rubidium-Noble Gas Mixtures via Collisional Redistribution of Radiation