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Chip-scale atomic magnetometer



P Schwindt, Svenja A. Knappe, V Shah, Leo W. Hollberg, John Kitching, Li-Anne Liew, John Moreland


Using the techniques of micro-electro-mechanical systems (MEMS), we have constructed a small, low-power magnetic sensor based on alkali atoms. By measuring the energy shift of the atoms' magnetic moment due to a magnetic field via a coherent population trapping resonance, we detect the magnetic flux density with a sensitivity of 50 pT Hz-1/2 at 10 Hz. The magnetic sensor has a size of 12 mm3 and dissipates 195 mW of power. Further improvements in size, power dissipation, and magnetic field sensitivity are immediately foreseeable, and such a device could provide a hand-held, battery-operated magnetometer with an atom shot-noise limited sensitivity of 0.05 pT Hz-1/2.
Applied Physics Letters


atomic sensors, coherent population trapping, magnetometry, MEMS


Schwindt, P. , Knappe, S. , Shah, V. , Hollberg, L. , Kitching, J. , Liew, L. and Moreland, J. (2004), Chip-scale atomic magnetometer, Applied Physics Letters, [online], (Accessed May 25, 2024)


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Created December 26, 2004, Updated October 12, 2021