title: Frequency-modulation spectroscopy of rubidium atoms with an AlGaAs diode laser.
abstract: Frequency-modulation (FM) spectroscopy has been performed on the D(2) transitions of rubidium atoms with an AlGaAs diode laser at 780 nm. Doppler-broadened hyperfine-structure transitions of (85)Rb and (87)Rb were resolved with no residual amplitude-modulation-induced background signal by modulating the injection current of the laser diode at a low frequency (20-50 MHz) compared with the Doppler width. To obtain Doppler-free spectra, we combined FM spectroscopy with saturation spectroscopy. The results show that the FM spectroscopy technique is sensitive and should be useful for high-resolution spectroscopy, although the resolution was instrument limited and unusual double peaks were observed.
authors.forename: S
authors.initials: S
authors.lastname: Nakanishi
authors.forename: H
authors.initials: H
authors.lastname: Ariki
authors.forename: H
authors.initials: H
authors.lastname: Itoh
authors.forename: K
authors.initials: K
authors.lastname: Kondo