Three-photon excitation of the 1 S 0 state of Pr 3+ (A)

Bowen Xie, Swapan Kumar Gayen

Mark E. Koch, A. W. Kueny, William E. Case

We have obtained efficient laser action from Pr-doped LaCl3 using a novel pumping method. Pump energy is coupled into the crystal through Pr ions in an excited state rather than the ground state. Excited-state absorption is made possible by a regenerative feedback process (the photon avalanche) utilizing cross relaxation to convert the energy of a single ion in a high-lying state into energy shared by multiple lower lying state ions.

Christopher G. Levey, Thomas J. Glynn, William M. Yen

G. Wittmann, R. M. Macfarlane

We have observed photon-gated photoconductivity in Pr:YAG, providing clear evidence for photoionization of the trivalent praseodymium ion in the solid state. Photoionization occurs by two-step absorption from (3)H(4)(1) ? (1)D(2)(1) followed by an excited-state absorption from (1)D(2) to the lowest component of the 4f5d configuration. The excitation spectrum of the photocurrent shows sharp (1)D(2) spectral features, providing unambiguous assignment of the photocurrent.

V. G. Gorshkov, S.G. Sherman, А. И. Михайлов

Felix R. Graf, Bernd H. Plagemann, Eric S. Maniloff +3 more

We demonstrate the temporal compression of photon echoes in frequency-selective materials by application of frequency-swept excitation pulses. Experimental results in Pr(3+):Y(2)SiO(5) for two- and three-pulse photon echoes are presented and compared with theory. A possible application to temporal reduction of optical data streams is shown.