No abstract

No abstract

No abstract

No abstract

No abstract

No abstract

Alkali adsorption on the (0001) surface of the monocrystalline α-Al 2 O 3 was studied by means of lasersimulated desorption. It was found that alkali atoms are adsorbed mostly on the centers with the surface concentration of about 10 13 cm −2 . Although the temperature dependence of surface coverage is consistent with the conventional Langmuir model for adsorption on the isolated centers, the estimated adsorption energy of about 1 eV is too large to account for the quantum yield of the photodesorption process, which is as high as 5×10 −5 . To resolve this contradiction we assumed that adsorption centers make up chains along the steps on the surface. Lateral interactions between neighboring adatoms were accounted for by means of methods developed for the Ising model. Theoretical results are in agreement with the experiment.

Granular films of alkali and coinage metals are the most popular objects for exploring plasmonic effects. They are easy to obtain via physical vapor deposition and to study via optical means. In this contribution we show several ways not only to record but also to modify the granular metal films using thermal and nonthermal optical effects.