title: Role of excitons in electron- and photon-stimulated desorption of neutrals from alkali halides.
abstract: Low-energy (5-15 eV) electron- and photon-stimulated desorption of KI(100) yields I2P3/2 and 2P1/2 with hyperthermal (0.3 eV) and thermal velocity components. The desorption threshold for both components is 5.3 eV and is correlated with the gamma3/2-exciton long-wavelength edge. Exciton decay at the surface directly produces I2P3/2 and 2P1/2 with hyperthermal velocity and is in competition with self-trapping. Spin memory of the gamma-exciton hole-component is also evident in the hyperthermal channel. An exciton mediated desorption mechanism is presented which is general in alkali halides.
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of technology, Atlanta 30332, USA.
authors.forename: A
authors.initials: A
authors.lastname: Alexandrov
authors.forename: M
authors.initials: M
authors.lastname: Piacentini
authors.forename: N
authors.initials: N
authors.lastname: Zema
authors.forename: A C
authors.initials: AC
authors.lastname: Felici
authors.forename: T M
authors.initials: TM
authors.lastname: Orlando