PIER Photon Science Colloquium: "First realization of an atomic x-ray laser"

by Nina Rohringer (Max Planck Advanced Study Group at CFEL)

Friday 20 Apr 2012, 13:15 → 15:00 Europe/Berlin

Bldg. 28c, SemR.

Since the invention of the laser fifty years ago, laser amplification of atomic transitions have been extended to increasingly high power and shorter wavelength. The photo-ionization based inner‐shell x‐ray basing scheme was first proposed in 1967, but due to the requirement of an extremely fast and intense x‐ray pump, could never be realized so far. We report the first successful demonstration of this scheme (N. Rohringer et al., Nature 481, 488 (2012)). Focusing pulses from an x-ray free-electron laser into a gas sample of neon, a transient population inversion of the 2p-1s transition is created by rapid inner-shell photoionization. Stimulated emission initially induced by fluorescence photons then resulted in saturated amplification of the Kα radiation. Results of our experiment and comparison with theory will be presented.