Colloquium

Thursday, October 26, 12:30-1:45 pm Kinard G01

Towards high-accuracy optical clocks based on highly charged ions

S. M. Brewer

Department of Physics, Colorado State University

Abstract: Optical clocks based on highly charged ions (HCIs) offer several promising avenues for the study of physics beyond the standard model. Among these are searches for time variation of the fine structure constant, α˙ /α, ultralight scalar dark matter, and tests of quantum electrodynamics (QED). Due to level crossings occurring in high charge states, narrow linewidth optically accessible transitions with a high sensitivity to α˙ /α are predicted in systems such as Pr10+. We plan to create HCIs in a compact electron beam ion trap (EBIT) and then transfer them to a cryogenic radiofrequency (rf) Paul trap where quantum-logic spectroscopy (QLS) will be performed. I will present an update on HCI production in a recently developed EBIT and results on precision spectroscopy on 9Be+ in our first-generation rf trap. In addition, I will present an update on the development of a Ba4+ quantum-logic clock for use as an improved optical frequency standard and a new optical fiber link between CSU and the NIST-WWV clock ensemble located in Fort Collins, CO.

Bio: Samuel Brewer is an Assistant Professor in the Department of Physics at Colorado State University.  His research group focuses on precision measurements on trapped highly charged ions (HCIs) for tests of fundamental physics.  HCIs provide a unique platform for investigating physics beyond the standard model including tests of quantum electrodynamics and searches for time-variation of the fundamental constants.  His research group combines techniques developed for quantum information processing, ion-based optical clocks, and optical frequency metrology to investigate physics beyond the standard model at the low-energy scale.  He received his B.S. degree from Appalachian State University in 2006 and his Ph.D. from the University of Maryland in 2012.  During his Ph.D., he studied HCIs at the National Institute of Standards and Technology (NIST) in Gaithersburg, MD.  From 2012 to 2019, he worked as a postdoctoral researcher in the NIST – Boulder Ion Storage Group.  While there, he developed an Al+ quantum-logic clock, which is the most accurate atomic clock in the world.

Light lunch will be served for those attending the colloquium in Kinard 114 at 11:30