DISPERSION OF NONLINEAR SUSCEPTIBILITY.
Abstract
The dispersion of the optical nonlinear susceptibility of semiconductors with 43m symmetry is discussed. The nonlinear susceptibility measures properties which are peculiar to mixed parity of band wavefunctions and which should contain information about the electronic structure that is complementary to that obtained from the dispersion of linear susceptibility. The magnitude of the nonlinear susceptibility for second-harmonic production has been measured, relative to KDP, in single crystal mirrors of GaAs, InAs, InSb, and ZnTe at nine different wavelengths. Pronounced maxima in the nonlinear susceptibility as a function of frequency is observed and can be correlated with the structure of the linear dielectric constants. These maxima in the nonlinear susceptibility are connected with critical points in the joint density of states of the band structure. The nonlinear susceptibility is complex when the medium is absorbing at either or both of the fundamental and harmonic wavelengths. In order to know the real and imaginary parts of the nonlinear susceptibility, one must know its phase as well as its magnitude. An experiment is described which determines the phase of the nonlinear susceptibility. This phase has been measured for GaAs, InAs, and ZnTe with the ruby laser. Another part of the talk deals with the verificationof several postulates of nonlinear optics. In particular, the nonlinear counterpart of laws for optical reflection and the analog of Brewster's angle for second-harmonic polarization. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1965
- Accession Number
- AD0479875
Entities
People
- Richard K. Chang
Organizations
- Harvard University