Heidelberg 2015 – wissenschaftliches Programm
A 35.16: Poster
Donnerstag, 26. März 2015, 17:00–19:00, C/Foyer
Narrowband Light Sources for optical Clocks of Ba+ and Ra+ — •Nivedya Valappol, Elwin A. Dijck, Andrew Grier, Klaus Jungmann, Amita Mohanty, Mayerlin Nuñez Portela, and Lorenz Willmann — Van Swinderen Institute, University of Groningen, The Netherlands
Narrow transitions in single ions such as Al+, Mg+, Sr+ and Hg+ are the basis for optical clocks. The ultra-narrow electric quadrupole transitions ns 2S1/2 * (n-1)d 2D5/2 in some isotopes of Ra+ (n=7) and Ba+ (n=6) are less sensitive to some of the major clock systematics. Narrowband lasers for the clock transitions (728nm in Ra+ and 1761.7nm in Ba+) and cooling transitions for state manipulation are required. These ion clocks will be compared via a 2x300km long fiber link between Groningen and the University of Amsterdam  with other stable frequency references. For the cooling transition at 650nm in Ba+ a diode laser is stabilized to a high finesse optical cavity in order to observe narrow Raman resonances and manipulate the internal state. The design is applicable to light sources for other transitions where laser diodes are available. In addition, the lasers provide for measurements of atomic parity violation in Ba+ and Ra+.
 T.J. Pinkert et al., arXiv:1410.4600 (2014)