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Summary form only given. The modern development of quantum optics began with the realization that the coherence properties and most of the statistical properties of light are determined by a succession of correlation functions for the quantized electromagnetic field. Many of the cold-atom experiments of the past decade that are part of the foundation of the new field of atom optics have close optical...
Summary form only given. Bosonic stimulation as the principal mechanism for the growth of a Bose-Einstein condensate was first introduced and quantitatively evaluated by Gardiner et al., and this was subsequently experimentally verified by Miesner et al. Although agreement between experiment and theory is not perfect, it is clear that the predicted mechanism of stimulated emission into the condensate...
Summary form only given. The transition between quantum and classical systems is usually ascribed to decoherence effects, which become increasingly important for larger size systems and tend to obscure the quantum behavior. Decoherence effects also come into play in the famous thought 'Gedanken' experiments on the wave-particle duality of matter. For example, in a double slit experiment with electrons,...
Summary form only given. The process of two atom superradiance has been investigated by trapping two dipoles at a mutual transverse distance R within a planar high-finesse microcavity. The peculiar time characteristics of superradiance consists of the doubling of the spontaneous emission rate with respect that of a single dipole if R is lower than the transverse extension of the confined electromagnetic...
Summary form only given, as follows. We report on the observation of narrow resonances associated with cold cesium collisions. A loss of laser cooled atoms in a trap is induced with a laser tuned to the blue of the 6S-6P transition. Several sharp resonances, with /spl sim/kHz intrinsic linewidths, are observed as a function of an applied magnetic field. The resonances appear near magnetically tunable...
Summary form only given. We have created state-selected /sup 87/Rb/sub 2/ molecules at rest in a dilute Bose-Einstein condensate of /sup 87/Rb atoms with coherent free-bound stimulated Raman transitions. The transition lineshape exhibits a resonance lineshape with an extremely narrow width as small as 1.5 kHz. As a result, we are able to measure the molecular binding energy with an unprecedented precision...
Summary form only given. The dilute gas experiments on the Bose-Einstein condensation of magnetically confined alkali vapors have already generated widespread interest across a broad spectrum of traditional fields of physics. They have provided an exciting stage on which to build bridges linking the theory of complex and collective phenomena in superconducting and superfluid systems with the single...
Summary form only given. Several theoretical studies have recently been published, proposing a new series of experiments involving two different species of atoms trapped together: two species BEC and heteronuclear cold collisions. As in the case of single species, these experiments require that samples be obtained at high density. Therefore, an important step is the understanding and possible control...
Summary form only given. We report on recent experimental and theoretical investigations of highly excited atoms prepared from a dense atomic sample in a magneto-optical trap (MOT). The goals of the work are two-fold. First, by exciting atoms above the ionization potential (IP) we can study the properties of an ultracold plasma of electrons (T<1 K) and ions (T<1 mK). Second, tuning the excitation...
Summary form only given. The investigation of coherent superposition states for atoms interacting with external potentials allows a completely new class of experiments directed towards coherent trapping and guiding of neutral atoms. In addition, the process of decoherence, i.e., the collapse of superposition states, is one of the basic concepts for our understanding of the connection between classical...
Summary form only given. Since the first observations of Bose Einstein condensates (BEC) in dilute atomic gases, there has been considerable interest in observing effects in atomic BEC akin to the hallmark effects associated with a superfluid, in particular persistent, quantized circulation of the fluid. Using a method proposed by Williams and Holland' we have prepared vortices, macroscopic quantum...
Summary form only given, as follows. Much (indeed most!) of quantum mechanics is concerned with determining the eigenvalues and eigenstates of the system of interest and scattering rates between these states. But in many cases (e.g. in superconductors and lasers) coherent superpositions of states are required to understand the physics. Furthermore some of the deepest issues of physics arise from correlations...
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