Abstract
The derivative of the reflectivity spectrum of InSb near the and peaks has been measured at 77°K with a double-beam wavelength-modulation method which emphasizes singularities in the dielectric constant, . The experimental line shapes of and cannot be explained as being due to the generally accepted (hyperbolic) critical points, but are intermediate between the line shapes for and critical points. This mixture of line shapes is, in view of our knowledge of the one-electron band structure of InSb, evidence for the contribution of the electron-hole interaction (exciton effects) to the observed optical spectra.
- Received 22 April 1968
DOI:https://doi.org/10.1103/PhysRev.174.828
©1968 American Physical Society