Bose-Einstein Condensation Lab

Investigators: Azure Hansen, Justin T. Schultz, and N.P. Bigelow (recent graduates)

The Bigelow group studies vortices in BECs both experimentally and theoretically. Our most recent experiments focus on spin textures and topological excitations of a spinor BEC, singular atom optics, and imaging the complex spinor wavefunction of a BEC. 

       

Bose-Einstein condensates are a quantum state of matter first described by S.N. Bose and A. Einstein in the 1920's, and achieved experimentally in a dilute atomic gas in 1995 by groups at JILA, MIT, and Rice. Their unique properties allow physicists to study a wide range of phenomena. For more information on how to make BECs and why they're so interesting, see, for example, the Nobel Lectures from 1997 and 2001, and NOVA's Absolute Zero site on ultracold atoms.

The Bigelow BEC lab's work presently revolves around complex spin textures in spinor becs. We engineer the phase and amplitude of each magnetic spin state of a Bose-Einstein condensate using a coherent two-photon stimulated Raman interaction. This allows us to create complex non-equilibrium spatially-dependent spin textures with specific spin and orbital (vortex) angular momenta. Depending on the choice of spin texture, we can study a wide range of phenomena, each connecting to a different field of physics. Since we are using Rubidium-87, we can create both spin-1 and spin-2 spin textures, as well as pseudo-spin systems. Our work both furthers fundamental understanding of spin-dependent symmetries and light-matter interactions, as well as extends applications of ultracold atomic physics to metrology and quantum information.


Our experiment uses 87-Rb (rubidum), a double magneto-optical trap (MOT) setup, a Ioffe-Prichard magnetic trap, and forced RF evaporative cooling to create a Bose-Einstein condensate of 5,000,000 atoms. We create vortices and spin textures in the BEC using a coherent two-photon stimulated Raman process, which requires microsecond laser pulses, tuned to the correct powers and frequencies to within microwatts and 10 MHz, respectively. We have developed a powerful numerical model to describe this Raman interaction. Our data is collected by absorption imaging, which gives us information about the density distribution of the atomic cloud in space; Stern-Gerlach imaging, which spatially separates the atomic cloud by its spin state; and matter-wave interference, which reveals the spatially-dependent phase of the condensate. 


Learn more 

Selected work 
  • Transfer and Storage of Optical Information in a Spinor Bose-Einstein Condensate
    A Hansen, L.S. Leslie, M Bhattacharya, and NP Bigelow
    Laser Science, LTuJ (2010)
  • 'Creation and detection of skyrmions in a Bose-Einstein condensate'
    L. S. Leslie, A. Hansen, K. C. Wright, B. M. Deutsch, N. P. Bigelow
    Phys. Rev. Lett. 103, 250401 (2009). Read on arxiv.
    'Erratum: Creation and Detection of Skyrmions in a Bose-Einstein Condensate [Phys. Rev. Lett. 103, 250401 (2009)].'
    L. S. Leslie, A. Hansen, K. C. Wright, B. M. Deutsch, N. P. Bigelow
    Phys. Rev. Lett. 107, 269902 (2011)
  • 'Dynamics of vortex matter in rotating two-species Bose-Einstein condensates' 
    S. J. Woo, S. Choi, L. O. Baksmaty, and N. P. Bigelow 
    Phys. Rev. A 75, 031604(R) (2007)
  • 'Excitation Spectroscopy of Vortex Lattices in a Rotating Bose-Einstein Condensate' 
    S. J. Woo, L. O. Baksmaty, S. Choi, and N. P. Bigelow 
    Phys. Rev. Lett. 92, 170402 (2004)
  • 'Spin-mixing dynamics of a spinor Bose-Einstein condensate'
    H. Pu, C.K. Law, S. Raghavan, J.H. Eberly, N.P. Bigelow 
    Phys. Rev. A 60, 1463 (1999)



Recent graduates



This work has been supported by The National Science Foundation (NSF), The Army Research Office (ARO) of the United States Army Research Laboratory (ARL), The Defense Advanced Research Projects Agency (DARPA) of The United States Department of Defense (DOD), and the NASA-JPL Physical Science Research Program Cold Atom Laboratory (CAL).