Optical transition of the 229^{229}229Th nucleus in a solid-state environment (original) (raw)

We describe a novel approach to directly measure the energy of the narrow, low-lying isomeric state in 229 Th. Since nuclear transitions are far less sensitive to environmental conditions than atomic transitions, we argue that the 229 Th optical nuclear transition may be driven inside a host crystal with a high transition Q. This technique might also allow for the construction of a solidstate optical frequency reference that surpasses the precision of current optical clocks, as well as improved limits on the variability of fundamental constants. Based on analysis of the crystal lattice environment, we argue that a precision of 3 × 10 −17 < ∆f /f < 1 × 10 −15 after 1 s of photon collection may be achieved with a systematic-limited accuracy of ∆f /f ∼ 2 × 10 −16. Improvement by 10 2 − 10 3 of the constraints on the variability of several important fundamental constants also appears possible.