Nonlinear Phenomena in Semiconductors through Multi-Photon Absorption.
Final rept. 1 Apr 71-31 Dec 73,
BOEING AEROSPACE CO SEATTLE WASH
Pagination or Media Count:
The research is a systematic study of both the experimental and theoretical aspects of the several nonlinear phenomena produced by CO2 laser irradiation of the narrow gap semiconductor InSb. The two-proton excitation rate at 2K and 77K is measured and calculated the agreement between experiment and theory is within the experimental accuracy. The electron-hole recombination coefficient is also measured and calculated, and a one to two order-of-magnitude discrepancy between the values is found. The investigation of this discrepancy has led to the discovery of a promising method for obtaining more precise information than yet available about the shape of the warped valence band in InSb. The properties of the excess carriers resulting from the two-photon excitation of electron-hole pairs are reported in detail. These properties include photoconductivity, infrared absorption, recombination radiation, stimulated emission, hot electron effect, Hall mobility and uniformity of carrier density along the irradiating beam. A new phenomenon is described pulse shaping of relatively high-intensity laser beams as they traverse the InSb crystal. This effect is explained in detail by nonlinear free-hole absorption. Author
- Solid State Physics