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[en] The Billiard Ball model is developed as a new way of visualizing many coherent transient phenomena. Several different aspects of the photon echo formation process are explained using this model and its extension, the Elliptical Billiard Ball model. The results of a series of experiments that verify some of the predictions of these models are presented. We observed in some of these experiments a dynamic range of nearly 12 orders of magnitude; it should be possible to observe echo intensities over even larger dynamic ranges
[en] We propose a method to control the atomic dynamics in the presence of electromagnetic fields. Instead of measuring the population dynamics, we focus on the possibility of controlling the Pancharatnam phase. For a two-level system we find that this phase can be optically induced and controlled by the phase shift. More importantly, the nonlinear interaction between the atom and the field leads to an enhanced sensitivity for the control of the atomic phase evolution and system dynamics.
[en] In this paper we study the evolution properties along with inversion phenomena of the resonance interactions of a single two-level atom with n-mode cavity fields. A general expression of the state for the n-mode field is presented. It is found that this atom-field interaction model obeys the Rabi oscillation
[en] Maximal entanglement between the atom and its spontaneous emission field is generated just by the rates of incoherent pumping fields. The effect of quantum interferences arising from incoherent pumping processes and spontaneous emission fields (decay induced interference) on atom-photon entanglement is discussed. The maximum atom-photon entanglement establishes when the population almost equally distributes among the bare states. No laser fields are used at any stage of the processes.
[en] Using the random matrix description of open quantum chaotic systems we calculate in closed form the universal autocorrelation function and the probability distribution of the total photodissociation cross section in the regime of quantum chaos. copyright 1998 The American Physical Society
[en] Photoassociation and the Feshbach resonance are, in principle, feasible means for creating a molecular Bose-Einstein condensate from an already-quantum-degenerate gas of atoms; however, mean-field shifts and irreversible decay place practical constraints on the efficient delivery of stable molecules using either mechanism alone. We therefore propose Feshbach-stimulated Raman photoproduction, i.e., a combination of magnetic and optical methods, as a means to collectively convert degenerate atoms into a stable molecular condensate with near-unit efficiency
[en] To apply the adiabatic rapid passage process repetitively [T. Lu, X. Miao, and H. Metcalf, Phys. Rev. A 71, 061405(R) (2005)], the nonadiabatic transition probability of a two-level atom subject to chirped light pulses over a finite period of time needs to be calculated. Using a unitary first-order perturbation method in the rotating adiabatic frame, an approximate formula has been derived for such transition probabilities in the entire parameter space of the pulses
[en] Strongly confining an ultracold atomic gas in one direction to create a quasi-two-dimensional system alters the scattering properties of this gas. We investigate the effects of confinement on Feshbach scattering resonances and show that strong confinement results in a shift in the position of the Feshbach resonance as a function of the magnetic field. This shift, as well as the change of the width of the resonance, is computed. We find that the resonance is strongly damped in the thermal gas, but in the condensate the resonance remains sharp due to many-body effects. We introduce a two-dimensional model system, suited for the study of resonant superfluidity and having the same scattering properties as the tightly confined real system near a Feshbach resonance. Exact relations are derived between measurable quantities and the model parameters