Livermore Group Reports Soft X‐Ray Laser

A group at Lawrence Livermore Laboratory has operated the first soft x‐ray laser. As proof, they have extensive diagnostics from more than 100 test shots showing not only that radiation emitted at two wavelengths near 20 nm were up to 700 times more intense than those from spontaneous emission, but also that these lines behaved in other ways characteristic of a laser. Group leader Dennis Matthews, together with Mordecai Rosen, presented Livermore's results at the Boston meeting of the APS Division of Plasma Physics last October. The announcement is a welcome milestone in the quest for an x‐ray laser, which has been underway since the first theoretical suggestions of x‐ray lasing schemes in the late sixties. Other participants in that search, now more confident of their own eventual success, can be expected to join Livermore in the drive towards greater efficiency, higher power and ever‐shorter wavelengths.