Is a gamma ray laser possible?

In theory, stimulated emission of annihilation radiation (511-keV photons) from positronium (a bound pair of electron and positron) is possible. See, for example, the paper at the following link at the University of California, Riverside. read more

The paper briefly discusses some of the attributes of such a gamma-ray laser. For instance, it will be a mirrorless device (unlike your garden-variety HeNe lasers) confining the positronium in a Bose-Einstein condensate. read more

For example, your gamma-ray laser may pass right through your target and only have a few photons even hit the target. This would make it a very bad weapon. Actually, that's what makes it a great weapon. read more

From microwave masers to terahertz, IR, visible, UV, and x-ray lasers, light sources based on gain media cover a wide spectral range. And, in case you ever wondered, gamma-ray lasers may be possible too. read more