Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Miniature atomic magnetometer integrated with flux concentrators



William C. Griffith, Ricardo Jimenez Martinez, Vishal Shah, Svenja A. Knappe, John E. Kitching


A major limitation on the sensitivity of alkali atomic magnetometers, spin-exchange relaxation, can be completely eliminated by operating at low magnetic field and high alkali density. This allows the miniaturization of atomic magnetometers while retaining exceptional sensitivity. We have previously demonstrated a spin exchange relaxation free magnetometer using a millimeter scale vapor cell that achieved magnetic field sensitivity of 70 fT/Hz1/2. The addition of magnetic flux concentrators around the vapor cell is used to further enhance the magnetic field sensitivity. Although limited at low frequencies by magnetic noise in the concentrator material, for frequencies above 100 Hz we reach a sensitivity of 15 fT/Hz1/2.
Applied Physics Letters


atomic magnetometer, magnetic flux concentrators, optical pumping, SERF


Griffith, W. , Jimenez, R. , Shah, V. , Knappe, S. and Kitching, J. (2009), Miniature atomic magnetometer integrated with flux concentrators, Applied Physics Letters, [online], (Accessed May 24, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created January 14, 2009, Updated February 19, 2017