Showing papers by "Hartmut Häffner published in 2002"
TL;DR: In this article, a Bose-Einstein condensate (BEC) in a one-dimensional optical lattice was used to perform band spectroscopy, where the BEC was loaded into the ground state with a very high efficiency by adiabatically turning on the lattice.
Abstract: We have performed a number of experiments with a Bose-Einstein condensate (BEC) in a one-dimensional optical lattice. Making use of the small momentum spread of a BEC and standard atom optics techniques, a high level of coherent control over an artificial solid-state system is demonstrated. We are able to load the BEC into the lattice ground state with a very high efficiency by adiabatically turning on the optical lattice. We coherently transfer population between lattice states and observe their evolution. Methods are developed and used to perform band spectroscopy. We use these techniques to build a BEC accelerator and a novel, coherent, large-momentum-transfer beam-splitter.
292 citations
TL;DR: The photoassociation rate constant increases linearly with intensity, even where it is predicted that many-body effects might limit the rate.
Abstract: We form ultracold ${\mathrm{Na}}_{2}$ molecules by single-photon photoassociation of a Bose-Einstein condensate, measuring the photoassociation rate, linewidth, and light shift of the $J\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$, $v\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}135$ vibrational level of the ${A}^{1}{\ensuremath{\Sigma}}_{u}^{+}$ molecular state. The photoassociation rate constant increases linearly with intensity, even where it is predicted that many-body effects might limit the rate. Our observations are in good agreement with a two-body theory having no free parameters.
132 citations
25 citations
TL;DR: In this paper, the magnetic moment of the electron bound in hydrogen-like oxygen O7+ has been determined using the "continuous SternGerlach effect" in a double Penning trap.
Abstract: The magnetic moment of the electron bound in hydrogen-like oxygen O7+ has been determined using the "continuous SternGerlach effect" in a double Penning trap. We obtained a relative precision of 2 x 109. This tests calculations of bound-state quantum electrodynamics and nuclear correction. PACS No.: 32.10Dk
17 citations
TL;DR: In this article, the electronic g-factor of a single hydrogen-like ion in its ground state was determined with a relative accuracy of 2 × 10−9, where the largest uncertainty results from the mass of the electron.
Abstract: We describe a double—Penning-trap experiment suitable for testing QED in strong fields by determining the electronic g-factor of a single hydrogen-like ion in its ground state. Our measurements on 12C5+ reach a relative accuracy of 2 × 10−9, where the largest uncertainty results from the mass of the electron. Together with equally precise theoretical predictions therefore, it is possible to evaluate a new value for the electron’s mass. The possibilities to obtain other fundamental constants and nuclear parameters are lined out.
15 citations
TL;DR: In this article, the electron's mass was derived from an experiment on the electronic g factor in 12C5+ and 16O7+ together with the most recent quantum-electrodynamical predictions.
Abstract: We present a derivation of the electron's mass from our experiment on the electronic g factor in 12C5+ and 16O7+ together with the most recent quantum-electrodynamical predictions. The value obtained from carbon reads me = 0.000 548 579 909 3(3) u, that from oxygen me = 0.000 548 579 909 2(5) u. The value from carbon agrees with the currently accepted one within 1.5σ but is four times more precise. The contributions to the uncertainties of our values are discussed. PACS Nos.: 14.60Cd, 06.20Jr, 31.30Jv, and 32.10Fn
2 citations