Medium Energy Physics Seminar

Conference Room R-150, Building 203, Argonne National Laboratory

Thursdays at 10:00 AM

Dong Sheng

NIST

Recent progress in vapor cell atomic magnetometry

Host: Zheng-Tian Lu

18 December 2014

I will report recent progress on vapor cell atomic magnetometers and co-magnetometers. The first part of the talk describes a Rb scalar gradiometer using two multipass optical cells. We use a pump-probe measurement scheme to suppress spin-exchange relaxation and reach sub-femtotesla magnetic field sensitivity. It approaches, for the first time, the fundamental limit set by Rb-Rb collisions. The second part of the talk reports recent progress in the development of a new co-magnetometer using He-3 and Xe-129 nuclear spins. The co-magnetometer is run as a clock by measuring the precession frequencies of the two nuclear spin species ''in the dark'', with Rb atoms used only to measure the initial and final phases of nuclear spin precession. Using this system we investigated several general classes of systematic effects affecting gas spin co-magnetometers, including thermal diffusion and quadratic magnetic field gradients. Current sensitivity of this co-magnetometer is promising for an improved precision measurement of spin-gravity couplings. I will also discuss possible experiments using the Xe-129/Xe-131 system.

Zheng-Tian Lu, Chairman (630-252-0583, [email protected] mail)

Debbie Beres, Secretary (630-252-4100, [email protected] mail)

---

Paul E. Reimer
[email protected]
31 March 2015