Title :
Influence of scattering and two-photon absorption on the optical loss in GaAs-Al2O3 nonlinear waveguides measured using femtosecond pulses
Author :
Rao, Soma Venugopal ; Moutzouris, Konstantinos ; Ebrahimzadeh, Majid ; De Rossi, Alfredo ; Gintz, G. ; Calligaro, Michel ; Ortiz, Valentin ; Berger, Vincent
Author_Institution :
Sch. of Phys. & Astron., Univ. of St. Andrews, Fife, UK
fDate :
3/1/2003 12:00:00 AM
Abstract :
The influence of scattering and two-photon absorption on the optical loss in GaAs-Al2O3 semiconductor nonlinear waveguides has been studied using femtosecond pulses. By deploying a scattering technique, loss coefficients were evaluated over an extended wavelength range of 1.3-2.1 μm in the near-infrared. A systematic study involving intensity and wavelength dependence of the loss revealed the presence of two-photon absorption for wavelengths below 1.6 μm. A simple nonlinear transmission study enabled the separation of the two-photon absorption coefficient from scattering and linear absorption. The calculated two-photon absorption coefficients were ∼9-20 cm/GW.
Keywords :
absorption coefficients; alumina; gallium arsenide; high-speed optical techniques; light scattering; optical frequency conversion; optical losses; optical waveguides; two-photon processes; 1.3 to 2.1 micron; GaAs-Al2O3; GaAs-Al2O3 nonlinear waveguides; extended wavelength range; femtosecond pulses; light scattering; linear absorption; loss coefficients; near-infrared; nonlinear frequency conversion; optical loss; scattering technique; two-photon absorption; two-photon absorption coefficient; wavelength dependence; Absorption; Frequency conversion; Loss measurement; Nonlinear optics; Optical losses; Optical pulses; Optical scattering; Optical waveguides; Pulse measurements; Ultrafast optics;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2002.808173
