Researchers at Princeton University have developed a novel high
sensitivity magnetometer having the ability to detect and measure very low
magnetic field intensities. The device relies on polarizing alkali
metal vapor, and probing the state of magnetization of the polarized metal atoms
to measure characteristics of a magnetic field originating from a variety of
sources.
The device is a radio-frequency tunable atomic magnetometer for detection
of nuclear quadrupole resonance (NQR) from room temperature solids, including
detection of nitrogen-containing explosives placed external to a sensor unit.
The potassium radio-frequency magnetometer has a sensitivity of 0.24
fT/Hz.sup.1/2 operating at 423 kHz. The magnetometer can detect a .sup.14N
NQR signal from room temperature ammonium nitrate (NH.sub.4NO.sub.3) in the
zero-applied field limit. Results demonstrate, for the first time,
detection of NQR with an atomic magnetometer, cryogen-free, with intrinsically
frequency-independent sensitivity and easy tuning capabilities, that can be used
for detecting magnetic resonance signals in the kHz to MHz range. Low intensity
magnetic fields can be measured using an alkali metal vapor, by increasing
magnetic polarization of the vapor to increase its sensitivity, then probing the
magnetic polarization of the vapor to receive an output, and determining
characteristics of the low intensity magnetic field from the output.
Patent protection has been granted under US #
7,521,928.
For
more information please contact:
William H. Gowen
Office of Technology Licensing and Intellectual
Property
Princeton University
4 New South Building
Princeton, NJ 08544-0036
(609) 258-6762
(609) 258-1159 fax
wgowen@princeton.edu