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Summary form only given. A type-II phase-marched parametric downconverter can be used to produce polarization-entangled photon pairs. We propose a production scheme for polarization-entangled photon pairs by using a pair of optical parametric amplifiers (OPAs) whose narrowband generation rate is high enough to make it a practical source for a trapped-atom quantum memory. For a type-II system using...
Summary form only given. Progress in cw optical parametric oscillators (OPOs) has been spurred by improvements and new developments in several areas during the last years: novel LiNbO/sub 3/ periodically poled (PP) crystals, powerful single-frequency pump sources, durable and broad-band dielectric coatings, frequency stabilization techniques, and novel device configurations.
Summary form only given. In any optical system, quantum and classical theory yield identical predictions for the mean intensity. The quantum mechanical predictions diverge from the classical theory only for higher order correlations. For this reason, typical quantum-interference experiments are performed by measuring coincidence rates between two or more detectors. The usual approximation, following...
Summary form only given. A single-mode quantum-phase operator cannot be simultaneously Hermitian and work in an unrestricted Hilbert-space, recently, work on finding the operator corresponding to the relative phase between two harmonic oscillators has been undertaken. In particular we suggested an experimental implementation of a generalization of the relative-phase operator derived by Luis and Sanchez-Soto...
Summary form only given. Recent studies have been carried out on the resonant response from single interface fluctuation quantum dots. Such a discrete-level model yields unique signatures under strong resonant driving, including Rabi oscillations. To date, Rabi oscillations (excluding microcavity studies) have only been reported for two-dimensional excitonic systems. We present data showing the nonlinear...
Summary form only given. A microscopic many-body theory for the optical and electronic properties of semiconductors is reviewed with an emphasis on the role of correlation effects among the electronic excitations and in the light matter coupling. The nonlinear response near the fundamental absorption edge and the light emission characteristics are studied for a variety of laser excited heterostructure...
Summary form only given. As we have shown recently, measurement of the polarization-sensitive phase of the quantum beats in time-integrated four wave mixing (FWM) signal provides us with a novel and effective tool here. The amplitude and phase of the oscillating TI-FWM signal are determined by the interplay of the four-particle correlation and mean field mechanisms of the optical nonlinearity at the...
Summary form only given. Four-wave mixing processes in semiconductor quantum wells have been studied intensively for many years, because they allow for a detailed investigation of ultrafast many-body processes such as quantum correlations and quantum coherences. From a theoretical point of view one can roughly divide the existing approaches into two categories: (i) fully microscopic theories based...
Summary form only given. There is considerable current interest in microlasers, both from a fundamental and from a practical point of view. The ultimate goal is to have a sufficiently small laser that /spl beta/, the fraction of the spontaneous emission going into the lasing mode, becomes equal to one. When approaching the /spl beta/=1 limit, the usual laser threshold disappears, and such devices...
Summary form only given. Absorption spectroscopy is widely used in the laboratory and for in situ measurements. One of the most important issues of any monitoring technique, as important as the sensitivity, is the ability to provide absolute absorption coefficients without the need for complicated and cumbersome calibration procedures. Intracavity-laser-absorption-spectroscopy (ICLAS) is one of the...
Summary form only given. We present a novel many-particle theory, which contains both of these methods as limiting cases. Our approach is based on the nonequilibrium Green's function (NGF) technique, which is applied to perform a detailed diagrammatic analysis of the various interaction processes. Biexcitonic correlations are obtained by renormalizing polarization scattering processes and the coherent...
Summary form only given. GaAs and AlGaAs have very large second-order susceptibilities. To achieve efficient frequency conversion, multilayers have been used to achieve quasi-phase matching (QPM). Although reflected-second-harmonic generation (SHG) in GaAs/Al/sub x/Ga/sub 1-x/As multilayers was initially studied, QPM in this geometry has not been achieved so far. Here, we report our results on detailed...
Summary form only given. A number of sophisticated techniques have been applied to precise measurements of the strength of resonance transitions in heavier alkali atoms. These include refined lifetime measurements in atomic beams, photoassociative spectroscopy of cold atoms confined to atomic traps, and direct measurements of the natural width of an atomic transition. We have made a precise study...
Summary form only given. Strong field molecular optics aims to control the position, velocity and acceleration, as well as the alignment, angular velocity and angular acceleration of a molecule. Molecular optics shares position control with atomic optics and optical tweezers. Rotation and dissociation are a distinctly molecular processes. Our experiments demonstrate that an extremely strong torque...
Summary form only given. Through many numerical, analytical and recently also experimental investigations it has been verified that the collapse of self-focusing femtosecond pulses propagating through normally dispersive bulk third-order media is arrested by temporal dispersion due to the positive value of the GVD constant. In simple intuitive terms the arrest of the collapse may be explained as follows:...
Summary form only given. Recent experiments have revealed ultrafast optically-induced dynamics in the time-resolved magneto-optical (MO) signals obtained in metallic ferromagnetic samples. The very short time scales that have been reported seem to exclude the role of spin-lattice interactions in the dynamics and open several fundamental questions about the physical mechanism responsible for fast demagnetization...
Summary form only given. Entangled states of multi-particle systems are arguably the quintessential feature of quantum mechanics. In addition to their central role in discussions of non-local quantum correlations, they form the basis of quantum information, and enable such phenomena as quantum cryptography, quantum dense coding, teleportation, and quantum computation. Via the process of spontaneous...
Summary form only given. High harmonic generation (HHG) in monatomic gases is well understood and small molecules have been found to behave in a similar way. The efficiency of harmonic generation is approximately predicted by the static polarisability of the species and the maximum harmonic order increases with the ionisation potential of the species and the ponderomotive potential of the laser field...
Summary form only given. Donor/acceptor substituted conjugated molecules possess even-order nonlinear polarizabilities. Existing experimental and theoretical studies have not yet established the precise scaling law of the second-order polarizability /spl beta/ and its the crossover to the bulk. In this paper we use a Collective Electronic Oscillator (CEO) technique to explore the variation of linear,...
Summary form only given. We report saturation of THz-radiation from femtosecond-laser irradiated InAs in a high magnetic field We have found the saturation of the THz-radiation power on the applied magnetic field. The optimum magnetic field was found to be 3 T. We have also observed interesting dependence of the frequency and the spectral width of the radiation.
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