Princeton University

Wonjae Lee

Michael Romalis

Mark Limes

Elizabeth Foley

Nezih Dural

Tom Kornack

Vito-Giovanni Lucivero

Tao Wang

Thomas Kornack

Vito Giovanni Lucivero

Atomic magnetometers are usually used as scalar sensors to measure the magnitude of the magnetic field. The magnetic field is converted to a frequency that can be measured with high fractional precision. There are no comparable methods for measuring vector magnetic field components. Common sensors, such as flux-gate and SQUID magnetometers, suffer from calibration and orthogonality uncertainty. Disclosed is a method of using an atomic magnetometer to measure the magnitude and two polar angles of the magnetic field vector. The two polar angles are dimensionless quantities and can be measured with high fractional precision. Also disclosed is a particular measurement procedure that is immune to systematic effects in such measurements.

Pulsed vector magnetometer using a fast rotating field

According to various embodiments, a method for reducing heading error in a magnetometer that uses Rb-87 atoms is disclosed. The method includes varying a direction and magnitude of a magnetic field at different spin polarization regimes. According to various embodiments, a magnetometer adapted for reduced heading error is disclosed. The magnetometer includes a multipass cell containing Rb-87 vapor, a pump laser operated in a pulse mode that is synchronous with a Larmor frequency, and two orthogonal probe lasers configured to rotate to vary a direction and magnitude of a magnetic field at different spin polarization regimes.

System and method for heading error correction in a pulsed Rb-87 magnetometer at geomagnetic fields

According to various embodiments, a direct magnetic gradiometer having intrinsic subtraction of rotation signals from two oppositely polarized atomic ensembles within a single multi-pass cell is disclosed. The gradiometer includes three convex spherical mirrors aligned in a V-shape geometry. The three convex spherical mirrors include a front mirror and two back mirrors. The gradiometer further includes a probe laser beam. The laser beam is configured to be initially focused at a near-zero angle into a hole at a center of the front mirror such that the laser beam expands at the back mirrors and nearly overlaps with itself while undergoing multiple reflections between the front and back mirrors. The laser beam is further configured to be refocused to the front mirror at different spots in a number equal to half of total beam passes before exiting.

System and method for femtotesla direct magnetic gradiometer using a multipass cell

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Princeton, NJ, United States of America

Wonjae Lee