Using photoelectron spectroscopy, we have observed alkali anion photodesorption from alkali-halide cluster anions that contain two weakly bound electrons. In the alkali iodides, we have found this type of desorption in almost every (MI)(n)M- cluster we have studied (M=Na, K, Cs; n<9), although it depends on the probe laser frequency and cluster temperature. Using pump-probe techniques, we have shown that the process occurs on a picosecond time scale by way of an electronic excitation of the cluster's spin-paired electrons.

Abstract:We demonstrate the use of cylindrical vector beams -beams with spatially varying polarization -for detecting and preparing the spin of a warm rubidium vapor in a spatially dependent manner. We show that a modified probe vector beam can serve as an atomic spin analyzer for an optically pumped medium, which spatially modulates absorption of the beam. We also demonstrate space-variant atomic spin by optical pumping with the vector beams. The beams are thus beneficial for making singleshot polarization-dependent measurements, as well as for providing a means of preparing samples with position-dependent spin. References and links 1.Q. Zhan, "Cylindrical vector beams: from mathematical concepts to applications," Adv. Opt. Photon. 1, 1-57 (2009

No abstract

Photoelectron spectra obtained from ͑CsX) 3 Cs Ϫ (XϭCl,Br,I͒ cluster anions are strongly dependent on the temperature of the laser vaporization source in which they were produced. Spectral features that were present in clusters emerging from the source at room temperature disappear when the source is cooled to low temperature. This effect is consistent with spontaneous thermal isomerization in the isolated clusters, a precursor to the melting transition in bulk materials.