title: Doppler-free two-photon transitions to Rydberg levels: convenient, useful, and precise reference wavelengths for dye lasers.
abstract: We used a tunable cw dye laser to observe Doppler-free two-photon transitions to alkali-atom Rydberg levels. Real-time signals were obtained in an ionization cell of appropriate construction. The two-photon transition wavelengths to rubidium s levels were measured up to n = 50 with better than 1 x 10(-7) absolute accuracy and can be represented to within the experimental precision by a simple function of the principal quantum number, Other related transitions and future possibilities are considered.
authors.forename: S A
authors.initials: SA
authors.lastname: Lee
authors.forename: J
authors.initials: J
authors.lastname: Helmcke
authors.forename: J L
authors.initials: JL
authors.lastname: Hall
authors.forename: B P
authors.initials: BP
authors.lastname: Stoicheff