Future Directions of Laboratory X-ray Laser Research

Abstract

Recently, gain-length products exceeding 8 have been achieved with the Ni-like (Ta and W),4d-4p x-ray laser scheme (MacGowan et. al. Phys. Rev. Lett. 65, 420 (1990)) with wavelengths just inside and just outside the water window, near the carbon K edge at 43.7 Å. This success, however, is tempered by the fact that it took two of the ten arms of Nova, the world's most powerful laser, to pump the exploding foils that served as the amplification medium. If applications of x-ray lasers are to become a reality, we must devote some thought and effort to schemes that can produce such short wavelength lasing using more user friendly and less costly facilities.