arXiv subjects

Harald R. Telle

Publications and source records attributed to Harald R. Telle.

3 recordsLinked to original sources

arXiv2001

Ultra-precise measurement of optical frequency ratios

We developed a novel technique for frequency measurement and synthesis, based on the operation of a femtosecond comb generator as transfer oscillator. The technique can be used to measure frequency ratios of any optical signals throughout the visible and near-infrared part of the spectrum. Relative uncertainties of $10^{-18}$ for averaging times of 100 s are possible. Using a Nd:YAG laser in combination with a nonlinear crystal we measured the frequency ratio of the second harmonic $ν_{SH}$ at 532 nm to the fundamental $ν_0$ at 1064 nm, $ν_{SH}/ν_0 = 2.000 000 000 000 000 001 \times (1 \pm 7 \times 10^{-19})$.

physics.optics↗

arXiv2001

Kerr-lens mode-locked lasers as transfer oscillators for optical frequency measurements

We introduce a novel concept for optical frequency measurement and division which employs a Kerr-lens mode-locked laser as a transfer oscillator whose noise properties do not enter the measurement process. We experimentally demonstrate, that this method opens up the route to phase-link signals with arbitrary frequencies in the optical or microwave range while their frequency stability is preserved.

physics.optics↗

arXiv2001

Absolute frequency measurement of the 171Yb+ clock transition with a Kerr-lens mode-locked femtosecond laser

We have measured the frequency of the $6s^2S_{1/2} - 5d^2D_{3/2}$ electric-quadrupole transition of $^{171}$Yb$^+$ with a relative uncertainty of $1\times 10^{-14}$, $ν_{Yb}$ = 688 358 979 309 312 Hz $\pm$ 6 Hz. A femtosecond frequency comb generator was used to phase-coherently link the optical frequency derived from a single trapped ion to a cesium fountain controlled hydrogen maser. This measurement is one of the most accurate measurements of optical frequencies ever reported, and it represents a contribution to the development of optical clocks based on an $^{171}$Yb$^+$ ion standard.

physics.optics↗