Photoassociation Spectroscopy of Laser-Cooled Ytterbium Atoms

Abstract

We report the photoassociation spectroscopy of laser-cooled ytterbium atoms in an optical trap. We observed more than 90 photoassociation resonances of vibrational levels in the (1)Sigma(+)(u) state, including 80 consecutive series, up to 490 GHz detuning with respect to the atomic resonance. From the resonance frequencies we derived the atomic radiative lifetime of the (6s6p) 1P1 state to be 5.464+/-0.005 ns, which is about 2 orders of magnitude improvement over previous results. We also observed line broadening of resonances, which is ascribed to the predissociation to the triplet states, and estimated the transition probability to be 0.2. Furthermore, we observed the decrease of the photoassociation signal intensity, from which the scattering length is estimated to be equal to or less than 3 nm.

Tune-out wavelengths for the alkaline-earth-metal atoms

“…The line strength, 17.25 (7), was taken as the average of the two photoassociation line strengths [56,57] and its uncertainty was dervied from the difference of the two values and the quoted uncertainty of Ref. [57]. The excitation energy for the 4f −1 6s 2 5d 1 P o 1 state is set to experiment.…”

“…In this model the line-strength and excitation energy for the resonant excitation energy are set to experimental values. The line strength, 17.25 (7), was taken as the average of the two photoassociation line strengths [56,57] and its uncertainty was dervied from the difference of the two values and the quoted uncertainty of Ref. [57].…”

Line shapes of optical Feshbach resonances near the intercombination transition of bosonic ytterbium

“…Quantum degenerate gases have been obtained for the bosonic isotopes 174 Yb [8], 170 Yb [9], and 176 Yb [10], and the fermionic isotopes 171 Yb and 173 Yb [11]. Photoassociation spectroscopy has been carried out for bosons [12,13] as well as fermions [14]. A two-color photoassociation experiment has allowed a precise determination of the ground state s-wave scattering lengths for all combinations of Yb isotopes [15].…”

Paramagnetic Faraday rotation with spin-polarized ytterbium atoms

“…Therefore, effectively N σ 0 L in the expression of φ becomes smaller and N σ 0 L = 2Sσ 0 /(πw 2 ) = 2 × 10 2 . The detuning of the probe beam was set at ω − ω (3/2) = 2π × 1.6 GHz, which was the blue detuning so as not to induce the photoassociation [22]. At this probe frequency, φ/pN σ 0 L is 3.8 × 10 −4 .…”