Strong Quantum Spin Correlations Observed in Atomic Spin Mixing

We have observed sub-Poissonian spin correlations generated by collisionally induced spin mixing in a spin-1 Bose-Einstein condensate. We measure a quantum noise reduction of -7 dB (-10 dB corrected for detection noise) below the standard quantum limit (SQL) for the corresponding coherent spin states. The spin fluctuations are detected as atom number differences in the spin states using fluorescent imaging that achieves a detection noise floor of 8 atoms per spin component for a probe time of 100 $\mu$s.Comment: 5 pages, 4 figure

Relative number squeezing in a Spin-1 Bose-Einstein condensate

The quantum properties of matter waves, in particular quantum correlations and entanglement are an important frontier in atom optics with applications in quantum metrology and quantum information. In this thesis, we report the first observation of sub-Poissonian fluctuations in the magnetization of a spinor 87Rb condensate. The fluctuations in the magnetization are reduced up to 10 dB below the classical shot noise limit. This relative number squeezing is indicative of the predicted pair-correlations in a spinor condensate and lay the foundation for future experiments involving spin-squeezing and entanglement measurements. We have investigated the limits of the imaging techniques used in our lab, absorption and fluorescence imaging, and have developed the capability to measure atoms numbers with an uncertainly < 10 atoms. Condensates as small as ≈ 10 atoms were imaged and the measured fluctuations agree well with the theoretical predictions. Furthermore, we implement a reliable calibration method of our imaging system based on quantum projection noise measurements. We have resolved the individual lattice sites of a standing-wave potential created by a CO2 laser, which has a lattice spacing of 5.3 µm. Using microwaves, we site-selectively address and manipulate the condensate and therefore demonstrate the ability to perturb the lattice condensate of a local level. Interference between condensates in adjacent lattice sites and lattice sites separated by a lattice site are observed.Ph.D.Committee Chair: Chapman, Michael; Committee Member: Bellissard, Jean; Committee Member: Brown, Ken; Committee Member: Curtis, Jennifer; Committee Member: Raman, Chandr

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc

International strontium optical lattice clocks comparisons with an optical fiber link

International audienc