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Updated: Jun 22, 2026

Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
Wavelength dependence of two photon and free carrier absorptions in InP
Leonel P Gonzalez1, Joel M Murray, Srinivasan Krishnamurthy
1Air Force Research Lab, Material and Manufacturing Directorate, Wright Paterson Air Force Base, Ohio 45433, USA. leo.gonzalez@gdit.com
Abstract:
Nonlinear absorption at 1.064 and 1.535 microm wavelengths by two photon and free carrier absorption processes in undoped and Fe doped InP has been investigated. Using picosecond and nanosecond duration lasers, a self-consistent set of the two photon and free carrier absorption coefficients are experimentally obtained through nonlinear transmission measurements for the first time. Reduced carrier recombination lifetime caused a decrease in nonlinear absorption of nanosecond duration laser pulses in Fe doped samples.
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