Isotope shifts of naturalSr+measured by laser fluorescence in a sympathetically cooled Coulomb crystal

Abstract

We measured by laser spectroscopy the isotope shifts between naturally occurring even isotopes of strontium ions for both the 5s 2 S 1/2 → 5p 2 P 1/2 (violet) and the 4d 2 D 3/2 → 5p 2 P 1/2 (infrared) dipole-allowed optical transitions. Fluorescence spectra were taken by simultaneous measurements on a two-component Coulomb crystal in a linear Paul trap containing 10 3 -10 4 laser-cooled Sr + ions. The isotope shifts are extracted from the experimental spectra by fitting the data with the analytical solution of the optical Bloch equations describing a three-level atom interacting with two laser beams. This technique allowed us to increase the precision with respect to previously reported data obtained by optogalvanic spectroscopy or fast atomic-beam techniques. The results for the 5s 2 S 1/2 → 5p 2 P 1/2 transition are ν 88 − ν 84 = +378(4) MHz and ν 88 − ν 86 = +170(3) MHz, in agreement with previously reported measurements. In the case of the previously unexplored 4d 2 D 3/2 → 5p 2 P 1/2 transition we find ν 88 − ν 84 = −828(4) MHz and ν 88 − ν 86 = −402(2) MHz. These results provide more data for stringent tests of theoretical calculations of the isotope shifts of alkali-metal-like atoms. Moreover, they simplify the identification and the addressing of Sr + isotopes for ion frequency standards or quantum-information-processing applications in the case of multi-isotope ion strings.

Precision measurement of the branching fractions of the5pP1/22state inSrLikforman1, Tugayé2, Guibal3 et al. 2016Phys. Rev. A19180View full textAdd to dashboardCite

“…This laser has a nominal linewidth of 70 kHz and it is stabilized against long term drifts by a transfer-lock technique using a scanning ring cavity referenced to the stabilized 711 THz laser-diode [41,42]. The feedback loop of the lock is, in our case, relatively slow (bandwidth ≃ 3 Hz) [43].…”

Large‐Scale Fabrication of Surface Ion Traps on a 300 mm Glass Wafer

“…[ 40 ] Infrared lasers are stabilized with a transfer lock scheme. [ 41 ] The frequency gap is filled up and fine tuning of the cooling beam frequency is obtained using a double‐pass acousto‐optic modulator (AOM). The beam is coupled in a single mode optical fiber and then focused at the ion position with typical power in the 2–50 μW range.…”

Quantum-Logic Detection of Chemical Reactions

“…Simultaneously, we use 1092 nm co-propagating light resonant with the D 3/2 → P 3/2 line to deplete the long-lived D state and maintain the cooling. Importantly we account for the ion's isotope shift during this initial cooling stage [61], which is particularly important for trapping of the low abundant (0.56%) 84 Sr + isotope. The 422 nm originates from a diode laser which is injected-locked to reference lasers.…”