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    Phase Coherence in a Driven Double-Well System

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    We analyze the dynamics of the molecular field incoherently pumped by the photoassociation of fermionic atoms and coupled by quantum tunnelling in a double-well potential. The relative phase distribution of the molecular modes in each well and their phase coherence are shown to build up owing to quantum mechanical fluctuations starting from the vacuum state. We identify three qualitatively different steady-state phase distributions, depending on the ratio of the molecule-molecule interaction strength to interwell tunnelling, and examine the crossover from a phase-coherent regime to a phase-incoherent regime as this ratio increases.Comment: 5 pages, 2 figure

    Bifurcations and bistability in cavity assisted photoassociation of Bose-Einstein condensed molecules

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    We study the photo-association of Bose-Einstein condensed atoms into molecules using an optical cavity field. The driven cavity field introduces a new dynamical degree of freedom into the photoassociation process, whose role in determining the stationary behavior has not previously been considered. The semiclassical stationary solutions for the atom and molecules as well as the intracavity field are found and their stability and scaling properties are determined in terms of experimentally controllable parameters including driving amplitude of the cavity and the nonlinear interactions between atoms and molecules. For weak cavity driving, we find a bifurcation in the atom and molecule number occurs that signals a transition from a stable steady state to nonlinear Rabi oscillations. For a strongly driven cavity, there exists bistability in the atom and molecule number

    A Molecular Matter-Wave Amplifier

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    We describe a matter-wave amplifier for vibrational ground state molecules, which uses a Feshbach resonance to first form quasi-bound molecules starting from an atomic Bose-Einstein condensate. The quasi-bound molecules are then driven into their stable vibrational ground state via a two-photon Raman transition inside an optical cavity. The transition from the quasi-bound state to the electronically excited state is driven by a classical field. Amplification of ground state molecules is then achieved by using a strongly damped cavity mode for the transition from the electronically excited molecules to the molecular ground state

    Input and output in damped quantum systems III: Formulation of damped systems driven by Fermion fields

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    A comprehensive input-output theory is developed for Fermionic input fields. Quantum stochastic differential equations are developed in both the Ito and Stratonovich forms. The major technical issue is the development of a formalism which takes account of anticommutation relations between the Fermionic driving field and those system operators which can change the number of Fermions within the system

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    The Lime Content of Rocks of The Upper Cretaceous System of Osborne County, Kansas

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    This report is the result of several weeks of intensive study and investigation in the field and in the laboratory. In making this study of the rocks of Osborne County, Kansas, the writer is concerned chiefly with the chemistry of the rooks rather than with their geological formation. He has not attempted to make a complete analysis of the rocks, but has limited his investigation in order to determine certain facts concerning their line content. He has attempted to determine the consistency of the percentage of lime in a given member in various parts of the county and also of different beds of a given member in the same locality. He has also investigated the possibility of the existence of limestone of a percentage sufficiently high to be used for cattle feeding and for the manufacture of lime. As far as the writer has been able to determine, there has been no such analysis made for this particular locality previous to this time
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