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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. We provide a powerful tool to describe near-field spectroscopic effects in thermal emission of light. Due to the possibility of measuring near-field spectra by using near-field optics techniques, the work could find applications in solid-state spectroscopy. It should also be helpful in modeling nanoscale radiative transfer of energy, where transfer through non-radiating modes...
Summary form only given. We have performed real-time and orientation resolved measurements of single fluorescent molecules (DiIC/sub 18/) in thin films of PMMA and polystyrene at ambient and reduced oxygen conditions. Fluorescent time trajectories of single molecules have been recorded using a two-channel near-field optical microscope, with 30-/spl mu/s real-time resolution.
Summary form only given. Optical parametric amplifiers (OPA) have been demonstrated previously as a system capable of generating strongly squeezed states. The output from these systems is typically a "vacuum squeezed state" where the beam has no coherent amplitude. Such squeezed states may be used to improve the performance of optical measurements limited by quantum noise, or as reported,...
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 optical response of self-assembled quantum dots (SAQDs) has been an area of extensive research in recent years, driven both by an interest in the basic physics of these strongly confined systems, and by the possibility of practical applications for such structures. There have been several studies of carrier relaxation in these systems, including differential transmission,...
Summary form only given. Self-assembled semiconductor quantum dots have found interest as gain materials for semiconductor lasers. While time-resolved studies on quantum dots have mainly focused on the spontaneous recombination dynamics, little is known about the dynamics of lasing and stimulated emission from the dots. In this contribution we investigate the dynamics of stimulated emission in self...
Summary form only given. There is considerable interest in the study of light emission from optical cavities whose dimensions are of the order of a wavelength in all three dimensions. Most work has been carried out on etched structures. We propose and demonstrate a novel method for the fabrication of GaAs semiconductor optical microstructures by self-organization during molecular beam epitaxial growth...
Summary form only given. An underlying premise of quantum computing is the preservation of system coherence over long time scales. Here, we report studies of atom-cavity dynamics wherein behavior observed is distinctively related to the ultraslow atomic decoherence found in one such system. In our experiment, the atomic decoherence time is four orders of magnitude longer than the empty-cavity lifetime,...
Summary form only given. Spectroscopy at single, localized excitons in semiconductor quantum structures is presently a very interesting field of research. Much attention is paid to single-dot spectroscopy on quasi-0D excitons, which are localized e.g., at well width fluctuations in ultrathin quantum wells or within self-assembled islands. The microscopic origin of three-dimensional quantum confinement...
Summary form only given. In photonic crystals with spatially periodic dielectric constants, a variety of novel optical and quantum optical phenomena are expected to be realized. One of their peculiar features is the presence of those electromagnetic eigenmodes with extremely small group velocities (group-velocity anomaly) that leads to the enhancement of various optical processes. The phase-matching...
Summary form only given. Optical phase is conjugate to the photon-number in quantum optics and therefore is important for nonclassical states in which the photon-number operator is reduced below the semiclassical shot noise limit, i.e., for photon-number squeezed states. Nonclassical emission from semiconductor lasers has the added facet that excess phase fluctuations are correlated with fluctuations...
Summary form only given. One of the most interesting subfields of quantum optics is cavity QED - where microcavities impose nontrivial boundary conditions on the quantized electromagnetic field and alter the matter-light interactions of quantum electrodynamics. One of the first predictions of this theory was the modification of atomic spontaneous emission rates, through the use of microcavities to...
Summary form only given. We recently proposed a new type of waveguide, the coupled-resonator optical waveguide (CROW), where an array of high Q resonators are coupled together. Under the tight-binding approximation, we found that the dispersion relation of a CROW can described by a coupling coefficient K and that its group velocity is greatly reduced. However, the concept of CROW is not necessarily...
Summary form only given. The existence of quantum confinement in semiconductor nanocrystals allows to regard them as nanocavities for the electronic wavefunctions. The quantization of energy levels inside such nanocrystals results in quantization of the corresponding optical transitions. In fact, the absorption and photoluminescence spectra of various semiconductor nanocrystals possess rather a molecular-like...
Summary form only given. There has been increasing interest in optical processes using strong-coupling and induced transparency, termed electromagnetically induced transparency (EIT). Although the idea of EIT started for resonant /spl and/h-scheme (Raman scheme), the idea has now been extended to far-off resonance Raman system. We have reported the spontaneous evolution of strong-coupling through...
Summary form only given. Temporal soliton pulses in optical fiber owe their usefulness as bits of optical information to their remarkable stability. Their particle-like behavior enables them to survive severe perturbations, like collisions with one another, spectral filtering, or even attenuation with subsequent amplification. Solitons will thus inevitably be generated from a wide range of initial...
Summary form only given. We analyze the spatiotemporal waveform evolution of self-focused high power femtosecond pulses with a three dimensional phase-retrieval cross-correlation technique. The FWHM beam diameter evolution for 8l0-nm, 270-fs pulses propagating in sapphire due to self-focusing. Within the experimental power range, the beams shrink on propagation, and no catastrophic beam collapse was...
Summary form only given. Single crystals of the polydiacetylene, poly[2,4-hexadiyne-1,6-diol-bis(p-toluenesulfonate)] (pTS) have been studied in the near resonant regime by transient absorption spectroscopy. We show the changes observed in the absorption spectra at short times surrounding the arrival of the 726-nm laser pulse. The experiment is performed by monitoring the transmission of a continuum...
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