5 papers
Improved Measurement of the Hydrogen 1S - 2S Transition Frequency
Christian G. Parthey, Arthur Matveev, Janis Alnis +14
We have measured the 1S - 2S transition frequency in atomic hydrogen via two photon spectroscopy on a 5.8 K atomic beam. We obtain Hz for t…
Long-distance remote comparison of ultrastable optical frequencies with 1e-15 instability in fractions of a second
Andre Pape, Osama Terra, Jan Friebe +8
We demonstrate a fully optical, long-distance remote comparison of independent ultrastable optical frequencies reaching a short term stability that is superior to any reported remo…
Phase- coherent comparison of two optical frequency standards over 146 km using a telecommunication fiber link
Osama Terra, Gesine Grosche, Katharina Predehl +5
We have explored the performance of two "dark fibers" of a commercial telecommunication fiber link for a remote comparison of optical clocks. The two fibers, linking the Leibniz Un…
Optical frequency transfer via 146 km fiber link with 10^{-19} relative accuracy
G. Grosche, O. Terra, K. Predehl +5
We demonstrate the long-distance transmission of an ultra-stable optical frequency derived directly from a state-of-the-art optical frequency standard. Using an active stabilizatio…
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…