Abstract
We describe a novel approach to directly measure the energy of the narrow, low-lying isomeric state in . Since nuclear transitions are far less sensitive to environmental conditions than atomic transitions, we argue that the optical nuclear transition may be driven inside a host crystal with a high transition . This technique might also allow for the construction of a solid-state optical frequency reference that surpasses the short-term stability 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 (short-term stability) of after 1 s of photon collection may be achieved with a systematic-limited accuracy (long-term stability) of . Improvement by of the constraints on the variability of several important fundamental constants also appears possible.
- Received 4 June 2009
DOI:https://doi.org/10.1103/PhysRevLett.104.200802
©2010 American Physical Society