arXiv subjects

Norval Fortson

Publications and source records attributed to Norval Fortson.

3 recordsLinked to original sources

arXiv2011

Frequency doubling and stabilization of a Tm,Ho:YLF laser at 2051 nm to a high finesse optical cavity

Light from a Tm,Ho:YLF laser operating at 2051 nm is frequency doubled then coupled into a high Fabry-Perot cavity with manufacturer quoted finesse in excess of 300,000. The frequency of the laser is stabilized using the Pound-Drever-Hall (PDH) method. A two channel feedback circuit allows for laser frequency stabilization with a bandwidth of 2 MHz. This laser system has been used to drive the 6S1/2 to 5D3/2 transition in 138Ba+, where a 2 ms laser-ion coherence times has been observed, demonstrating a linewidth of less than 500 Hz. The intensity noise of this system is analyzed and found to be acceptable for several proposed experiments on a single trapped barium ion.

physics.ins-det↗

arXiv2005

Progress on indium and barium single ion optical frequency standards

We report progress on 115In+ and 137Ba+ single ion optical frequency standards using all solid-state sources. Both are free from quadrupole field shifts and together enable a search for drift in fundamental constants.

physics.atom-ph↗

arXiv2004

Possibility of an ultra-precise optical clock using the $6 ^1S_0 \to 6 ^3P^o_0$ transition in $^{171, 173}$Yb atoms held in an optical lattice

We report calculations designed to assess the ultimate precision of an atomic clock based on the 578 nm $6 ^1S_0 --> 6 ^3P^o_0$ transition in Yb atoms confined in an optical lattice trap. We find that this transition has a natural linewidth less than 10 mHz in the odd Yb isotopes, caused by hyperfine coupling. The shift in this transition due to the trapping light acting through the lowest order AC polarizability is found to become zero at the magic trap wavelength of about 752 nm. The effects of Rayleigh scattering, higher-order polarizabilities, vector polarizability, and hyperfine induced electronic magnetic moments can all be held below a mHz (about a part in 10^{18}), except in the case of the hyperpolarizability larger shifts due to nearly resonant terms cannot be ruled out without an accurate measurement of the magic wavelength.

physics.atom-ph↗