Ra⁺ ion trapping:toward an atomic parity violation measurement and an optical clock

A single Ra+ ion stored in a Paul radio frequency ion trap has excellent potential for a precision measurement of the electroweak mixing angle at low momentum transfer and as the most stable optical clock. The effective transport and cooling of singly charged ions of the isotopes Ra-209 to Ra-214 in a gas filled radio frequency quadrupole device is reported. The absolute frequencies of the transition 7s(2)S(1/)2-7d(2)D(3/2) at wavelength 828 nm have been determined in Ra-212-214(+) with ≤19 MHz uncertainty using laser spectroscopy on small samples of ions trapped in a linear Paul trap at the online facility Trapped Radioactive Isotopes: µicrolaboratories for fundamental Physics (TRIµP) of the Kernfysisch Versneller Instituut.