We report the observation of coexisting Bose-Einstein condensate (BEC) and Fermi gas in a magnetic trap. With a very small fraction of thermal atoms, the 7Li condensate is quasipure and in thermal contact with a 6Li Fermi gas. The lowest common temperature is 0.28 microK approximately 0.2(1)T(C) = 0.2(1)T(F) where T(C) is the BEC critical temperature and T(F) the Fermi temperature. The 7Li condensate has a one-dimensional character.

Broadband noise on supercontinuum spectra generated in microstructure fiber is shown to lead to amplitude fluctuations as large as 50% for certain input laser pulse parameters.We study this noise using both experimental measurements and numerical simulations with a generalized stochastic nonlinear Schrödinger equation, finding good quantitative agreement over a range of input pulse energies and chirp values. This noise is shown to arise from nonlinear amplification of two quantum noise inputs: the input pulse shot noise and the spontaneous Raman scattering down the fiber. * Work of an agency of the U.S. government; not subject to copyright.

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We demonstrate a robust method of stabilizing a diode laser frequency to an atomic transition. This technique employs the Zeeman shift to generate an antisymmetric signal about a Doppler-broadened atomic resonance, and therefore offers a large recapture range as well as high stability. The frequency of a 780-nm diode laser, stabilized to such a signal in Rb, drifted less than 0.5 MHz peak-peak (1 part in 10(9)) in 38 h. This tunable frequency lock can be constructed inexpensively, requires little laser power, rarely loses lock, and can be extended to other wavelengths by use of different atomic species.