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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 squeezing of an optical field is normally observed in the frequency domain using balanced homodyne detection to measure the fluctuation variance of a selected quadrature amplitude. The scheme amounts to a measurement of sub-Poissonian photon statistics and is sensitive to efficiencies as any such unconditional measurement is. Conditional measurements are independent of...
Summary form only given. We define the premise of "macroscopic local realism" so that its failure is more surprising than failure of the local realism addressed previously. Macroscopic local realism is a premise stating the following. If one can predict the result of a measurement at A by performing a simultaneous measurement on a spatially separated system B, then the result of the measurement...
Summary form only given. Nanoscale structures can be tailored to provide enhanced, nanoscale near-field optics. For example, high-quality GaAs quantum dots can be fabricated by self-formed growth near the apex of AlGaAs tetrahedral pyramids. Photoluminescence studies have shown a thousand-fold enhancement of the far-field emission of an embedded quantum dot. This large enhancement arises because the...
Summary form only given. Near stop-band edges, periodically microstructured media (photonic crystals) exhibit strong temporal and spatial dispersion. The challenge is to demonstrate very low out-of-plane leakage while preserving the advantages offered by photonic crystals. Among the devices being actively worked on are waveguides which are modeless within a range of frequencies, vertical emitting...
Summary form only given. Introducing a line defect into a photonic crystal can create localized states within the photonic band gap of the crystal. Such a defect behaves as a waveguide, where the confinement of the light occurs via the photonic band gap (PBG) rather than total internal reflection. Aside from some recent optical experiments, most qualitative studies of photonic crystal waveguides have...
Summary form only given. The use of planar microcavity structures to control spontaneous emission from optical devices is now a well-established technique. The simplest geometry is that of a pair of planar mirrors separated by a distance of order the wavelength of light, with the emissive species situated between the two mirrors. It has been clearly demonstrated that the boundary conditions imposed...
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. Reversible phase change materials such as compounds of the pseudo-binary GeTe-Sb/sub 2/Te/sub 3/ system are applicable as high-density optical data storage media based on the relatively high difference in the reflection coefficients of the amorphous and the crystalline states. Although this principle is already employed in commercial DVD disks, the physics of the phase transitions...
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. Because of their small nanometer size and strong electronic confinement, quantum dots exhibit zero-dimensional electronic and optical effects which continue to be interesting for physics and promising for applications. To study single and clusters of self-organized semiconductor quantum dots, near-field optical nanoprobing is a powerful tool. Its spatial resolution surpasses...
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. Laser cooling and trapping of atoms has enabled some of the most exciting recent advances in atomic physics, including the achievement of Bose-Einstein condensation (BEC). Efforts are now underway to trap ultracold molecules in order to study chemical reactions and to investigate BEC of larger particles. In the atomic BEC experiments, the atoms are cooled to sub-/spl mu/K...
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. For most values of magnetic field, very cold /sup 85/Rb atoms have a large negative scattering length and large loss rates from magnetic traps. The latter makes it difficult to cool the atoms low enough to achieve Bose-Einstein condensation (BBC), while the former constrains the size of a possible BEC to <100 atoms. However, we have found that near the Feshbach resonance...
Summary form only given. A system of indirect (interwell) excitons in coupled quantum wells (CQWs) provides a unique opportunity for experimental study of two-dimensional light composite bosons thermalized down to ultralow temperatures. The long recombination lifetime of indirect excitons promotes the exciton accumulation in the low energy exciton states and allows the system to cool down to temperatures...
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...
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