Strong extreme-ultraviolet fluorescence originating from core-excited autoionizing levels of neutral Rb is observed. Radiative branching ratios approaching unity are inferred from the radiative yields. Long autoionizing lifetimes and fast radiative rates make these levels promising candidates for extreme-ultraviolet laser systems.
© 1989 Optical Society of America
J. K. Spong, A. Imamog¯lu, J. D. Kmetec, and S. E. Harris, "Extreme-ultraviolet fluorescence from core-excited levels of neutral rubidium," Opt. Lett. 14, 168-170 (1989)