Patent ID: 8212556
Filing Date: 2012-07-03
Classification: G01R

Abstract:
1. An atomic magnetometer for sensing a magnetic field, comprising: a cell containing an alkali metal vapor; a pump light beam having a first wavelength which is substantially equal to the wavelength of a first D-line atomic transition of the alkali metal vapor, and with the pump light beam being directed through an optical waveplate and through the cell containing the alkali metal vapor to magnetically polarize the alkali metal vapor; a probe light beam having a second wavelength which is different from the first wavelength, with the second wavelength being substantially equal to the wavelength of a second D-line atomic transition of the alkali metal vapor, and with the probe light beam being directed through the optical waveplate and through the cell containing the alkali metal vapor to undergo a change in polarization due to the magnetic field; an optical filter located in a path of the pump light beam and the probe light beam, with the optical filter blocking transmission of the pump light beam and transmitting the probe light beam; and at least one photodetector to detect the probe light beam after transmission through the optical filter and to generate therefrom an electrical signal which depends upon the change in polarization of the probe light beam due to the magnetic field.