Miniature atomic magnetometer integrated with flux concentrators
William C. Griffith, Svenja A. Knappe, John E. Kitching, Ricardo Jimenez Martinez, Vishal Shah
High permeability magnetic flux concentrators are used to enhance the sensitivity of an atomic magnetometer operating in the spin exchange relaxation free regime. The magnetometer uses a millimeter scale 87Rb vapor cell and either mu-metal or Mn-Zn ferrite flux concentrators. The measured sensitivity gives excellent agreement with calculations of thermal noise from the concentrator material. The mu-metal concentrators allow a sensitivity of 50 fT Hz-1/2, limited by thermal current magnetic noise. The ferrite concentrators are limited by thermal magnetization noise at low frequencies, and reach a sensitivity of 10 fT Hz-1/2 for frequencies above 125 Hz.
, Knappe, S.
, Kitching, J.
, Jimenez, R.
and Shah, V.
Miniature atomic magnetometer integrated with flux concentrators, Applied Physics Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=900965
(Accessed December 4, 2023)