58 citations · 171 across the 10 of their papers we have counts for
11 papers
An Al clock with systematic uncertainty and its frequency ratios
Fabian Dawel, Johannes Kramer, Derwell Drapier +15
Advances in optical clocks motivate a redefinition of the second, requiring rigorous evaluations of systematic uncertainties and robust consistency among the clocks. Here, we repor…
A high-stability optical clock based on a continuously ground-state cooled Al ion without compromising its accuracy
Fabian Dawel, Lennart Pelzer, Kai Dietze +12
Single ion optical clocks have shown systematic frequency uncertainties below , but typically require more than one week of averaging to achieve a corresponding statistic…
Entanglement-enhanced optical ion clock
Kai Dietze, Lennart Pelzer, Ludwig Krinner +11
Entangled states hold the promise of improving the precision and accuracy of quantum sensors. We experimentally demonstrate that spectroscopy of an optical clock transition using e…
Multi-ion frequency reference using dynamical decoupling
Lennart Pelzer, Kai Dietze, Víctor J. Martínez-Lahuerta +6
We present the experimental realization of a continuous dynamical decoupling scheme which suppresses leading frequency shifts in a multi-ion frequency reference based on $^{40}\mat…
Coherent photo-thermal noise cancellation in a dual-wavelength optical cavity for narrow-linewidth laser frequency stabilisation
Fabian Dawel, Alexander Wilzewski, Sofia Herbers +7
Optical resonators are used for the realisation of ultra-stable frequency lasers. The use of high reflectivity multi-band coatings allows the frequency locking of several lasers of…
Phase-stabilized UV light at 267 nm through twofold second harmonic generation
Benjamin Kraus, Fabian Dawel, Stephan Hannig +3
Providing phase stable laser light is important to extend the interrogation time of optical clocks towards many seconds and thus achieve small statistical uncertainties. We report…
Towards a Transportable Aluminium Ion Quantum Logic Optical Clock
S. Hannig, L. Pelzer, N. Scharnhorst +7
With the advent of optical clocks featuring fractional frequency uncertainties on the order of and below, new applications such as chronometric levelling with few-cm hei…
Multi-mode double-bright EIT cooling
Nils Scharnhorst, Javier Cerrillo, Johannes Kramer +4
We developed a multi-mode ground state cooling technique based on electromagnetically-induced transparency (EIT). By involving an additional ground and excited state, two individua…
Experimental and theoretical investigation of a multi-mode cooling scheme using multiple EIT resonances
Nils Scharnhorst, Javier Cerrillo, Johannes Kramer +4
We introduce and demonstrate double-bright electromagnetically induced transparency (D-EIT) cooling as a novel approach to EIT cooling. By involving an additional ground state, two…
On-Line Estimation of Local Oscillator Noise and Optimisation of Servo Parameters in Atomic Clocks
Ian D. Leroux, Nils Scharnhorst, Stephan Hannig +4
For atomic frequency standards in which fluctuations of the local oscillator (LO) frequency are the dominant noise source, we examine the role of the servo algorithm that predicts…
High-bandwidth transfer of phase stability through a fiber frequency comb
Nils Scharnhorst, Jannes B. Wübbena, Stephan Hannig +4
We demonstrate phase locking of a 729 nm diode laser to a 1542 nm master laser via an erbium-doped-fiber frequency comb, using a transfer-oscillator feedforward scheme which suppre…