Frequency Dependent Dielectric Properties of Lead-Tin-Telluride.
Abstract
The authors report on the use of reflectivity measurements in the far infrared to obtain information on frequency and spatial dependence of the dielectric function of a Pb(0.82)Sn(0.18)Te epitaxial film. Reflectivity data were taken at near normal incidence from approximately 20/cm to 320/cm at 77K and at room temperature. The data consisted of the usual restrahl band plus a region of oscillations resulting from Fabry-Perot effect in the film and extending from approximately 120/cm to 320/cm. These oscillations provided that most abundant information on the dielectric function. The data were analyzed using the conventional 'two-oscillator' dielectric function including phonon and plasma damping. The spatial dependence of the dielectric function associated with the film substrate interface was accounted for by allowing for spatial dependence of the plasma frequency omega sub p. Two four-parameter analytical functions and a simple step (three-parameter) function were used to mode omega sub p(x).
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 26, 1975
- Accession Number
- ADA006968
Entities
People
- J. A. Cape
- W. E. Tennant