Lorraine Sadler
University of California at Berkeley
Tuesday, December 5, 2006
2:00 pm in SPL 52 Note different room
Spontaneous Symmetry Breaking and Defect Formation in a Quenched Ferromagnetic Spinor Bose-Einstein Condensate
Abstract: I will present our observation of spontaneous symmetry breaking in a spinor Bose condensate of 87Rb that is quenched across a quantum phase transition to a ferromagnetic state. Using non-destructive imaging techniques, we make high spatial resolution maps of the vector magnetization of the condensate. We observe the spontaneous formation of inhomogeneous ferromagnetic regions separated by un-magnetized defects. The growth of these ferromagnetic regions are due to a dynamical instability, which determines their typical size and the time for their formation in accord with our observations. I will also present our imaging of polar-core spin vortices, a topological defect seen in over one-third of all images, a consequence of quenching the system. Finally, I will discuss the application of the non-destructive imaging technique to precision magnetometery.