Sensor Technology for Anti-Submarine Warfare

This SBIR Phase I proposal describes the development of a conceptual design for a high-sensitivity laser magnetometer for ASW using Optically-driven Spin Precession (OSP). The OSP laser magnetometer is an innovative high-sensitivity instrument capable ofmeasuring scalar DC and ELF magnetic fields with a sensitivity better than 0.3 pT/root-Hz. The OSP laser sensor employs Optically-driven Spin Precession (OSP) instead of conventional Magnetically-driven Spin Precession (MSP) to induce and observe magneticresonance in the helium cell. An OSP single-cell digital locked-oscillator scalar magnetometer was demonstrated for the first time under a recent NASA Phase I Project achieving 3 pT/root-Hz sensitivity. Under this SBIR project the sensitivity will beimproved by one order of magnitude for ASW applications through laser noise reduction. A design will be developed to miniaturize the OSP sensor by eliminating the resonance drive coil and cable and obtaining full sensitivity on all headings using a singlehelium cell thereby reducing the number of helium cells from three to one for omni-directional operation. The feasibility of fabricating a high sensitivity breadboard OSP magnetometer in Phase II will be established under the Phase I Project. The OSPmagnetometer will have a variety of commercial and military applications including measurements of the magnetic fields around the Earth including monitoring the solar magnetic field activities for telecommunication applications and climate changepredictions. The OSP Magnetometer will be use at the Earth's surface for airborne and surface geomagnetic prospecting as well as unexploded ordinance detection (UXO). The laser magnetometer technology is currently being considered by the US Navy and theJapanese Defense Agency for submarine detection and for mine countermeasures applications. The OSPM capabilities of outstanding accuracy, high-sensitivity scalar measurements, omni-directionality without dead zones, and high-frequency detection will openup a variety of applications in commercial security and surveillance applications.