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Femtosecond pump-probe measurements are shown to reveal the evolution of excited vibrational wave packets in CS2 through the probe transmission modulation. Frequency-resolved acquisition allows for selective monitoring of different subsets of the Raman transitions excited.

We introduce a novel technique that elegantly combines frequency-and time-resolved CARS spectroscopy. The proposed scheme is tested in back-scattered CARS experiments on a powder of sodium dipicolinate, holding promise for remote/stand-of detection applications.

We have experimentally demonstrated an ultra-dispersive atomic prism with the highest spectral angular dispersion ever shown (six orders of magnitude higher than glass prism). Its dispersion is optically controlled by a coherent driving field.

We report the experimental observation of EIT in Cs2 in Lambda configuration. The width of EIT is smaller than widths of molecular transitions and has different dependence on temperature. Application to quantum storage is discussed.

We show that spectral hole refilling can be used to detect stimulated Raman scattering to determine vibrational frequency of molecules. The technique can be applied to spore detection and tissue microscopy.

We suggest a new efficient method of generation of intense (micro-J) short (fs-ns) THz pulses via coherent scattering of infrared radiation in atomic and molecular gases (f.e. Rb, methanol, and others) at room temperature.

We have experimentally observed switching between photon-photon correlations (bunching) and anti-correlations (anti-bunching) between two orthogonally polarized laser beams in an EIT configuration in Rb vapor. The bunching and anti-bunching sswitching occurs at a specific magnetic field strength.

We demonstrate how a strong coherent backward wave can be generated by forward propagating beams only. It is a dispersion effect resulting from probing a counter-propagating coherence grating by properly detuned fields.

Electromagnetically induced coherence can significantly increase optical response of atomic or molecular system. We demonstrate very large magneto-chiral anisotropy by applying resonant optical fields to atomic rubidium vapor.

We have experimentally demonstrated CARS scattering in the forward and backward directions. The signal observed in the backscattered is of the orders of magnitude stronger than would be expected.

We simulate the preparation of laser-induced vibrational coherence in the femtosecond time scale. By optimizing that coherence one can maximize the molecular CARS signal.

Summary form only given. A large temporal (frequency) dispersion accompanying electromagnetically induced transparency (EIT) leads to drastic slowing down of the group velocity of light, v/sub g/=c/(wdn(w))/dw/spl Lt/c has been shown in recent experiments. We show that by using spatial dispersion, which is due to an atomic motion, it is possible to freeze the light, i.e. to bring it to a complete stop or even reverse the direction of its propagation. We consider two different types of atomic motion: (i) uniformly moving atoms, i.e. atomic beam or uniformly moving sample, and (ii) atomic gas with a thermal distribution of the velocities in the cell which is at rest.

Summary form only given. All the schemes of lasers without inversion (LWI) which so far have been realized experimentally involve external coherent field driving some auxiliary transition in three- or four-level atomic system. In this paper we prove that steady-state lasing without inversion via decay induced coherence in the closed four level atomic system is possible.

Summary form only given. Recently, it was predicted that laser radiation can be used to manipulate very efficiently nuclear transitions at gamma-ray energies in solids. It results in both drastic qualitative and strong qualitative modifications of the Mossbauer spectra under the action of coherent optical radiation. The solid sample represents a host matrix where high densities of the ions are embedded by doping. The ions should possess both Mossbauer gamma-ray and optical electronic transitions favorable for the desired effects to be observed. Basically one needs Mossbauer-active ions with strong and sharp optical lines. The latter condition is typically satisfied for rare-earth and transition-metal ions in crystalline hosts and, remarkably, the majority of them are also Mossbauer-active.

The gamma-ray laser dilemma states that incoherent pump required to produce a population inversion would unavoidable destroy the conditions of the Mossbauer and Borrmann effects which are crucial for realization of the net gain. For four decades this dilemma prevailed all over the researches on gamma-ray lasers, making hopeless any attempt to approach a problem of gamma-ray laser. Recently it was shown that laser driving of bounded electronic transitions in atoms provides efficient manipulation by the Mossbauer spectra of nuclear transitions. Under certain conditions it leads to suppression of resonant absorption by 3-5 orders of magnitude reducing it up to the level of off-resonant losses in the host matrix. In turn, suppression of the resonant absorption reduces by the same amount the requirement for incoherent pump and accordingly heating of the active sample. This allows to pump active nuclei in the host lattice without destroying the conditions of both Mossbauer and Borrmann effects. Moreover it allows to pump resonantly at the operating transition that increases additionally the efficiency of the incoherent pump by 1-2 orders of magnitude. All together gamma-ray laser schemes involving laser driving of electronic transitions reduce the laser threshold by 4-7 orders of magnitude and hence suggest a completely new path for solution of the gamma-ray laser problem.

This study presents experimental results on quantum interference phenomena observed in gamma-optics for the first time. The idea is to employ the interference phenomena typical for electromagnetically induced transparency found in quantum optics.

Summary form only given. We develop the enhancement of coherent anti-Stokes Raman scattering (CARS) in terms of maximizing the coherence by stimulated Raman adiabatic passage and chirped pulse adiabatic rapid passage. This technique can be readily extended to a femtosecond time scale for rapid identification and trace of impurities.