Upconversion of laser radiation to gamma-ray energies

The coherent pumping of electromagnetic transitions in nuclei with intense optical radiation was modeled in this work. The anti-Stokes upconversion of conventional laser radiation was shown to be a potentially viable means for pumping a gamma-ray laser. It was found that the most favorable possible arrangement of nuclear energy levels, the threshold for stimulated output at 10 KeV might be reached at a few tens of Joules, for isomeric media with lifetimes of the order of tens of years. Whether such an arrangement of excited states actually exists will require additional experimentation. The overall possibilities for the excitation of a gamma-ray laser with optical pumping were concluded to be reasonably encouraging, and the need for additional spectroscopic data was clearly defined.