Abstract

The spectroscopy of dilute vapours is ordinarily limited by Doppler broadening. By using two counterpropagating light beams from the same laser, it is possible to get over this limit, and to attain true natural widths. Some methods use the saturation of ordinary one-photon transitions, and permit the selection of the signal given by the particular class of atoms whose velocity is perpendicular to the light beams: Lamb-dip spectroscopy, self-saturated absorption or dispersion, polarization spectroscopy. The second possibility is to produce double-photon transitions (E 2 - E 1 = 2hv) in such a manner that the Doppler shifts of the two photons exactly cancel each other, and all the atoms undergo the transition together for the true value of the laser frequency: Doppler-free multiphoton spectroscopy.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.