Accurate Evaluation of Nonlinear Absorption Coefficients in InAs, InSb and HbCdTe Alloys (Postprint)
Abstract
We present a full band structure calculation of temperature- and wavelength-dependent two-photon absorption (TPA) coefficients and free carrier absorption (FCA) cross sections in InAs, InSb, and Hg1−xCdxTe alloys. Although the wavelength dependence of the TPA coefficients agrees well with Wherrett expression, the accurately calculated values are smaller by a factor of 1.2 to 2.5. In addition, the TPA coefficient depends sensitively on the photoexcited carrier density in small gap material. The FCA is dominated by holes. The FCA cross section is independent of carrier density, but is strongly dependent on temperature. The calculated coefficients and lifetimes are fitted to closed form expressions and used in solving the rate equation to obtain the transmitted pump and probe intensities as functions of incident intensity and sample thickness. The calculated pump transmission and time-dependent probe transmission in InAs agree very well with the measured values.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 06, 2007
- Accession Number
- ADA473809
Entities
People
- Leonel P. Gonzales
- Shekhar Guha
- Srinivasan Krishnamurthy
- Zhi G. Yu
Organizations
- SRI International