title: Spectroscopic observation of the rotational Doppler effect.
abstract: We report on the first spectroscopic observation of the rotational Doppler shift associated with light beams carrying orbital angular momentum. The effect is evidenced as the broadening of a Hanle electromagnetically induced transparency coherence resonance on Rb vapor when the two incident Laguerre-Gaussian laser beams have opposite topological charges. The observations closely agree with theoretical predictions.
authors.affiliation: Facultad de Ingeniería, Instituto de Física, C. Postal 30, 11000 Montevideo, Uruguay.
authors.forename: S
authors.initials: S
authors.lastname: Barreiro
authors.forename: J W R
authors.initials: JW
authors.lastname: Tabosa
authors.forename: H
authors.initials: H
authors.lastname: Failache
authors.forename: A
authors.initials: A
authors.lastname: Lezama