ResearchResearch Area B
Research propject B0A

Project B0A: Tests of the equivalence principle with Yb+

The Yb+ ion possesses two forbidden electronic transitions that are suitable as references for an optical clock: an electronic quadrupole (E2) and an electronic octupole transition (E3). The higher sensitivity of the E2-frequency to shifts induced by external electric and magnetic fields can be used for the highly precise diagnosis and correction of shifts on the E3 frequency. The optical clock based on the E3 transition has been realized with an uncertainty in the low 10-18 range. At the same time, the excited state of the E3 transition (an electron hole in the 4f shell) shows a high sensitivity to relativistic effect because of its high angular momentum and proximity to the nucleus. This makes it possible to perform the presently most sensitive experiments searching for variations of the fine structure constant or a violation of Lorentz symmetry for electrons.


PUBLICATIONS

All publications of the Collaborative Research Centre

PROJECT LEADER

PD Dr. Ekkehard Peik
Address
PTB, Bundesallee 100
38116 Braunschweig
Address
PTB, Bundesallee 100
38116 Braunschweig