Ytterbium LITS
Frequency
Standards Laboratory
- The very short wavelength of the pumping light for the
mercury LITS (198 nm, a value almost in the vacuum ultraviolet) precludes
practical laser excitation at the present time. However, the linear trap
technology can be used to contain other ions with more practical pumping
requirements. Of particular interest is the 171 Ytterbium isotope which
has a hyperfine splitting of 10.64 GHz and an optical pumping requirement
of 369 nm, a wavelength easily achievable by frequency doubling available
lasers.
Tests on the laser-excited Ytterbium LITS clearly show
the advantages of laser excitation, including high signal strength, very
low background and laser cooling. JPL tests show that a previously observed
unwanted transition of the Ytterbium ions into a "Dark State"
can be alleviated by use of a nitrogen buffer gas.
For More Information
JPL Quantum Sciences and Technology Group