The optical constants and dielectric functions of a series of samples of glassy carbon subjected to a heat treatment from 1000°C to 3000°C have been evaluated in the spectral region of 1.5–13.8 eV. In the region of 1.5–5.0 eV the method of spectroscopic ellipsometry and multiangle reflectivity with p-polarized light was applied, while in the VUV region the optical constants were evaluated by means of multiangle reflectivity with partially polarized light as well as by means of Kramers–Kronig analysis. The optical spectra are discussed, in analogy with graphite, in terms of single-electron transitions and π electron plasma excitations. The changes in the spectra by heating are ascribed to increasing average size of ordered regions and sample densification in the absence of three-dimensional graphitization.
Heat treatment of glassy carbon implanted with cesium at room and high temperatures
