Bulletin of the American Physical Society

Electron impact excitation of laser-excited rubidium atoms

Zuyi Wei, Charles M. Flynn, Bernhard Stumpf

Published May 1, 1993• 0 citations

Abstract

A rubidium beam is intersected at right angles by a cylindrical electron beam and a counterpropagating, circularly polarized diode-laser beam, tuned to the F{sup {prime}} = 3 {r_arrow} F = 4 hyperfine transition of the 5{sup 2}S{sub 1/2} resonance line (780 nm) of {sup 85}Rb. Optical pumping creates {sup 85}Rb 5{sup 2}P atoms in a pure spin and angular momentum state {vert_bar}F=4, M{sub F}=4{r_angle} = {vert_bar}J=3/2, M{sub J}=3/2{r_angle}={vert_bar}M{sub L}=1, M{sub S}=1/2{r_angle}. Electrons of a few eV energy collide with these laser-excited rubidium atoms and excite them further to an upper state n{sup {prime}}L{sup {prime}}J{sup {prime}} from which they decay back to the 5{sup 2}P state. This n{sup {prime}}L{sup {prime}}J{sup {prime}}{r_arrow}5{sup 2}P fluorescence is detected to determine the 5{sup 2}P{sub 3/2,3/2}{r_arrow}6{sup 2}D{sub 3/2,5/2} excitation will be presented.

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