Physical Review A
Frequency Modulation in the Spectroscopy of an Inhomogeneously Broadened Line
Fujio Shimizu
Abstract
The effect of frequency modulation on an inhomogeneously broadened line is studied when the modulation frequency or amplitude is larger than the homogeneous width but less than the inhomogeneous width. It is shown that the deviation from the instantaneous response for the polarization disappears as a result of the averaging effect when the field intensity is weak.