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Summary form only given. Nowadays, a measurement of the intensity of the optical field in integrated optical waveguide devices with a photon scanning tunneling microscope (PSTM) is reasonably routine. However, if one could visualize the evolution of the phase of the light field in real-space, it would yield new and detailed information concerning the properties of wavelength multiplexers, mode converters,...
Summary form only given. Correlated and entangled single photon states have made possible many fundamental studies in quantum optics such as the Bell-type test of hidden variables and non-locality, explorations of quantum interference properties, and investigations of quantum information processing and quantum communications technologies such as quantum cryptography, quantum computing, and quantum...
Summary form only given. Several measurement methods of nonlinear optical Kerr coefficient n/sub 2/ in optical fibers have recently been proposed, bringing into evidence the different contributions of the electronic and electrostrictive parts, respectively n/sub 2k/ and n/sub 2e/, where electrostriction plays an important role at optical modulation frequency lower than 1.5 GHz, and is intrinsically...
Summary form only given. Four-particle correlation mediated by the Coulomb interaction has been found to play a major role in the nonlinear optical response at the semiconductor band edge at low excitation density. The attractive interaction of the excitons with opposite spins result in the formation of bound (bi-exciton) and unbound (scattered) two-exciton states. In this paper we report on the first...
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. Quantum coherence effects in atomic media interacting with multiple coherent electromagnetic fields have gained a lot of attention in both theoretical and experimental quantum optics over the last three decades. The absorptive and dispersive properties of coherently prepared media lead. Astonishing effects like electromagnetically induced transparency on extremely narrow dark...
Summary form only given. We present experimental results on the transfer of the orbital angular momentum of light to a system of cold cesium atoms. A four-wave-mixing process was used as an indirect tool to observe this transfer. We have observed the transfer of optical angular momentum (OAM) of light from an optical beam to the system of cold cesium atoms. We use the non-degenerate four-wave mixing...
Summary form only given. We present a novel technique in cavity ringdown spectroscopy that permits 1/spl times/10/sup -10/ absorption sensitivity with microwatt level light power. Heterodyne detection is employed between two alternating cavity modes, with one of them interacting with a molecular resonance.
Summary form only given. Noise immune cavity enhanced optical heterodyne molecular spectroscopy has been used to investigate (211) band of water vapor. To our knowledge this is the first high resolution, precision measurement of the water transitions in this region using ultrasensitive detection methods.
Summary form only given. Liquid hydrogen is the simplest molecular liquid known as a quantum liquid. The unique feature of liquid hydrogen is that the H/sub 2/ molecules consisting of the liquid have well-defined vibrational and rotational quantum states as free molecules. Here, we treat the liquid hydrogen as a nonlinear Raman medium for droplet nonlinear optics and carry out stimulated Raman scattering...
Summary form only given. Since the pioneering experimental results of optical vortex solitons have been in the centre of interest because of their fundamental importance in optics and other fields of physics, and because of their potential applications for all-optical information processing. Formally conventional vortex solitons exist on an infinite nonzero background, which in practice requires rather...
Summary form only given. The dynamics of phonon-polaritons generated with ultrafast pulses has been an active area of investigation in the past decade. Efforts have been concentrated on the wide-gap perovskites that undergo phase transformations associated with the softening of an optical phonon in order to determine what roles anharmonicity and photon-phonon coupling play in structural phase transitions...
Summary form only given. Intense investigations of Bloch oscillations in semiconductor superlattices have been performed in four-wave mixing, THz emissions and resonant transmittive electro-optic sampling experiments. An intriguing objective of the studies is the experimental determination of the spatial amplitude of the oscillating electronic wavepackets in the artificial heterostructures. We present...
Summary form only given. Bloch oscillations (BO) of electrons in a periodic system under applied electric field are a very basic transport effect and have been investigated in several experiments in semiconductor superlattices. In time resolved optical experiments, BO were studied by the excitation of wave packets of Wannier-Stark ladder (WSL) states and detection of four-wave mixing signals, THz...
Summary form only given. In solid state materials which lack a center of symmetry, cascaded second order nonlinear optical effects, namely the combination of optical rectification and the linear electro-optic effect, are a very important contribution to DFWM. We have demonstrated that the contributions of acoustic phonons must be taken into account in order to be able to compare DFWM experiments performed...
Summary form only given. Devices using quantum wires (QWR) are of much current interest. In recent times, several investigations have focussed attention on optical properties of QWRs at high excitation densities. In comparison, studies of excitonic interactions in QWRs are few. We perform femtosecond degenerate four wave mixing (DFWM) and picosecond photoluminescence measurements at 8 K on GaAs/AlAs...
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