title: Note: laser frequency shifting by using two novel triple-pass acousto-optic modulator configurations.
abstract: We report the design of two novel triple-pass acousto-optic modulator systems. These designs are extensions of the well known acousto-optic modulator (AOM) double-pass configuration, which eliminates the angle dependence of the diffracted beam with respect to the modulation frequency. In a triple-pass system, however, the frequency dependence of the angle does not disappear but the frequency shift is larger, spanning 3 times the AOM central frequency. In some applications, such as optically pumped Cesium-beam frequency standards, the frequencies of the two laser beams remain fixed and a triple-pass optical system can be used to reduce to one the number of lasers used in such atomic clocks. The two triple-pass configurations use either a retro-reflecting mirror, or a right angle prism to pass for third time the laser beam through the AOM, obtaining diffraction efficiencies of about 27% and 44%, respectively.
authors.affiliation: División de Tiempo y Frecuencia, Centro Nacional de Metrología, El Marqués, Querétaro 76246, México. edlopez@cenam.mx
authors.forename: E
authors.initials: E
authors.lastname: de Carlos-López
authors.forename: J M
authors.initials: JM
authors.lastname: López
authors.forename: S
authors.initials: S
authors.lastname: López
authors.forename: M G
authors.initials: MG
authors.lastname: Espinosa
authors.forename: L A
authors.initials: LA
authors.lastname: Lizama