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Updated: May 8, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Magic frequencies in atom-light interaction for precision probing of the density matrix
Menachem Givon1, Yair Margalit, Amir Waxman
1Ben-Gurion University of the Negev, PO Box 653, Beer Sheva 84105, Israel. givonme@bgu.ac.il
Abstract:
We analyze theoretically and experimentally the existence of a magic frequency for which the absorption of a linearly polarized light beam by a vapor of alkali-metal atoms is independent of the population distribution among the Zeeman sublevels and the angle between the beam and a magnetic field. The phenomenon originates from a peculiar cancellation of the contributions of higher moments of the atomic density matrix, and is described using the Wigner-Eckart theorem and inherent properties of Clebsch-Gordan coefficients. One important application is the robust measurement of the hyperfine population.
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