Nonclassical states of light and atomic ensembles: Generation and new applications

This thesis considers several novel methods for generating nonclassical states of light and atomic ensembles, and describes applications of these methods to precision measurements, generation of Fock states with controllable waveform and few-photons nonlinear optics.; We study the generation of spin-squeezed states of an ensemble of N atoms, and the conditions necessary to achieve high degree of squeezing taking into account imperfections such as decay and finite number of atoms. A specific implementation of this model based on atom-atom interactions via quantized photon exchange is presented in detail.; We analyze the effect of realistic noise sources for an atomic clock consisting of a local oscillator that is actively locked to a spin-squeezed (entangled) ensemble of N atoms. We show that the use of entangled states with a moderate degree of entanglement yields the maximal clock stability.; We study the dynamics of Raman scattering in optically thick atomic media, and the ensuing correlations between the atomic spin coherence and the Stokes photons created via Raman generation. The theoretical model and experimental highlights are presented, demonstrating generation of pulses of light with controllable photon numbers, propagation direction, timing, and pulse shapes.; We describe two methods to dynamically control the propagation of light in atomic media using EIT. We show that propagating light pulses can be coherently converted into stationary excitations with nonvanishing photonic components, and present high-lights of an experiment demonstrating this effect. We then show that these ideas can be further extended to localize optical pulses in all three spatial dimensions, and to dramatically enhance nonlinear interactions between weak optical pulses. Finally, we report on experimental progress towards nonlinear optical interactions in atomic media confined inside hollow-core photonic crystal fibers. We describe the experimental setup used to load Rubidium atoms along with a buffer gas inside the optical fiber, and report our preliminary results towards achieving this goal.