Surface plasmon modes and energy loss function of indium thin films on mica substrates

Abstract

Thin indium films of thickness ranging from 15 to 100 nm are deposited onto crystalline mica substrates under a pressure of 1.333 x lo-* Pa. Using ellipsometry the real and imaginary parts of dielectric constant and energy loss function -1m ( 1 /~) and -1m ( 1 / (~ + 1)) are calculated. Low energy peaks are interpreted in terms of interband transitions while high-energy peaks are interpreted in terms of surface plasmon oscillations. Dunne Indiumschichten mit einer Dicke zwischen 15 und 100 nm werden auf kristallinen Glimmersubstraten unter einem Druck von 1,333 x P a aufgebracht. Mittels Ellipsometrie werden Real-und Imaginiirteil der Dielektrizitiitskonstante und Energieverlustfunktionen -1m (1/e) und -Im ( 1 / (~ + 1)) berechnet. Die Niederenergiemaxima werden mit Interbandiibergiingen interpretiert, wiihrend die Hochenergiemaxima mit Oberfliichenplasmonoszillationen erklirt werden.

Thickness Dispersion of Surface Plasmon of Ag Nano-thin Films: Determination by Ellipsometry Iterated with Transmittance Method

“…The bulk plasmon frequency can be expressed in terms of the free electron density ( ρ ), the electron charge ( e ) and effective mass ( m* ): . Similar to the observation for indium thin film case 20 , by increasing the film thickness the free electron density increases to reach the value of bulk silver, which agrees with the observed increasing metallic behavior with thickness as deduced from the optical constants shown in Fig. 3 .…”