0822671_Phillips

1. Topological Semimetal in a Fermionic Optical Lattice William D. Phillips, University of Maryland College Park, PHY/DMR 0822671 Ultracold atomic gases trapped by laser light have become a playground for exploring quantum matter and even uncovering new phenomena not yet seen in nature. PFC researchers at JQI have shown that this kind of optical lattice system can exhibit a never-before-seen quantum state called a topological semimetal. This state can also undergo a new type of phase transition to a topological insulator.  Harnessing the underlying phenomena of topological insulators, known as quantum Hall physics, is important for developing new types of electronics and quantum information. Each atom in the lattice is represented by two dumbbells that cross (its p orbitals). This work opens the physics associated with such orbitals in optical lattices.

2. Second USA Science and Engineering Festival William D. Phillips, University of Maryland College Park, PHY/DMR 0822671 The Second USA Science and Engineering Festival was held at the Washington Convention Center national Mall on April 27 to 29, 2012. The PFC@JQI and the JQI joined the NIST booth and had a physics demonstration: The levitating superconductor (a magnetic rail made with strong permanent magnets creates a potential where the high temperature superconductor levitates and moves until it becomes normal, illustrating in a dramatic way the Meisner effect. Thousands of people passed through the booths in the three days while graduate students, postdoctoral associates, and faculty provided explanations.