title: Doppler-free two-photon heterodyne spectroscopy by single-beam frequency modulation.
abstract: A new spectroscopic method for monitoring Doppler-free two-photon absorption signals is analyzed. Its principle consists of high-frequency modulation of one of the incident beams and the detection of the modulation induced by two-photon absorption in the intensity of the counterpropagating beam. The predictable advantages of this method are pointed out by comparing it with other techniques.
authors.forename: M
authors.initials: M
authors.lastname: Ducloy