James K Thompson - "Twists, Gaps, and Superradiant Emission on a Millihertz Transition"

Stanford University
APPLIED PHYSICS/PHYSICS COLLOQUIUM

Tuesday, January 29, 2019
4:30 p.m. on campus in Hewlett Teaching Center, Rm. 201

James K. Thompson
JILA and Dept. of Physics, University of Colorado, Boulder

"Twists, Gaps, and Superradiant Emission on a Millihertz Transition"

I will describe superradiant pulses of light generated from an optical transition that does not normally like to radiate light: the millihertz linewidth optical transition in strontium. This new source of light may allow us to break through long standing thermal and technical limitations on laser frequency stability. The pulses of light are generated by laser cooling and trapping an ensemble of strontium atoms inside a high finesse optical cavity to achieve a large collective enhancement in the radiation rate. We also observe cavity-mediated spin-exchange interactions that manifest as one-axis twisting dynamics and the opening of a many-body energy gap. The spin-exchange interactions may prove useful for creating entanglement between the atoms and enhancing atomic coherence times.