Optical control and entanglement of atomic Schrodinger fields

We develop a fully quantized model of a Bose-Einstein condensate driven by a Far off-resonant pump laser and interacting with a single mode of an optical ring cavity. This geometry leads to the generation of two condensate side modes that grow exponentially and are strongly entangled with the cavity mode. By changing the initial state of the optical field one can vary the quantum-statistical properties of the atomic side modes between thermal and coherent limits, as well as vary the degree of quantum entanglement. [S1050-2947(99)50603-3].