One step closer to being able to turn on and off the decay of a nuclear isomer

Researchers at Livermore studied an isomer of Thorium-229. This isomer is unique in that its excitation energy is near optical energies, implying that one day scientists may be able to transition Th229 nuclei between the ground and isomeric states using a table-top laser.

"This would then be the first time human control would be exerted over nuclear levels," said Peter Beiersdorfer, an LLNL physicist and co-author of a paper that appears in the April 6 issue of Physical Review Letters. "This only works if the laser is tuned to exactly the correct energy."

The next step will be to use a laser or a synchrotron tuned to the exact energy of the spacing between the two levels and observe the transition from the ground state to the isomeric state.

Once laser excitation has proven possible, helping an excited level decay (and thus give off energy) can be tackled. "But for building a more precise clock than we have today, or building a quantum computer, excitation may be all that’s needed," Beiersdofer said.

This could lead to new science and technology breakthroughs. Among them are: a quantum many-body study; a clock with unparallel precision for general relativity tests; a superb qubit (a quantum bit) for quantum computing; testing the effects of the chemical environment on nuclear decay rates