30 citations · 105 across the 7 of their papers we have counts for
7 papers
A low repetition rate optical frequency comb
Francesco Canella, Johannes Weitenberg, Muhammad Thariq +6
Reducing the pulse repetition rate of an optical frequency comb increases the pulse energy for a given average power. This enhances the efficiency of nonlinear frequency conversion…
Observation of positronium annihilation in the 2S state: towards a new measurement of the 1S-2S transition frequency
D. A. Cooke, P. Crivelli, J. Alnis +8
We report the first observation of the annihilation of positronium from the 2S state. Positronium (Ps) is excited with a two-photon transition from the 1S to the 2S state where its…
Low phase noise diode laser oscillator for 1S-2S spectroscopy in atomic hydrogen
N. Kolachevsky, J. Alnis, C. G. Parthey +3
We report on a low-noise diode laser oscillator at 972 nm actively stabilized to an ultra-stable vibrationally- and thermally compensated reference cavity. To increase the fraction…
Measurement noise floor for a long-distance optical carrier transmission via fiber
G. Grosche, O. Terra, K. Predehl +6
We investigated the measurement floor and link stability for the transfer of an ultra-stable optical frequency via an optical fiber link. We achieved a near-delay-limited instabili…
Photoionization Broadening of the 1S-2S Transition in a Beam of Atomic Hydrogen
N. Kolachevsky, M. Haas, U. D. Jentschura +7
We consider the excitation dynamics of the two-photon \sts transition in a beam of atomic hydrogen by 243 nm laser radiation. Specifically, we study the impact of ionization dampin…
Precision study of hyperfine structure in simple atoms
S. Karshenboim, S. Eidelman, P. Fendel +4
We consider the most accurate tests of bound state QED theory of the hyperfine splitting in two-body atoms related to the HFS interval of the 1s state in muonium and positronium an…