Open AccessNear-infrared non-degenerate two-photon absorption coefficients of bulk GaAs and Si
Author(s) -
Laura Krauß-Kodytek,
Claudia Ruppert,
Markus Betz
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.433953
Subject(s) - attenuation coefficient , degenerate energy levels , two photon absorption , materials science , absorption (acoustics) , photon energy , photon , degeneracy (biology) , semiconductor , polarization (electrochemistry) , band gap , infrared , molecular physics , optics , condensed matter physics , atomic physics , physics , optoelectronics , laser , chemistry , bioinformatics , quantum mechanics , biology
We investigate the non-degenerate two-photon absorption coefficient β(ω 1 , ω 2 ) as a function of the non-degeneracy parameter ω 1 /ω 2 for bulk GaAs and Si at a constant transition energy ℏ ω 1 + ℏ ω 2 =1.57eV. In both materials, the two-photon absorption strength increases with increasing ω 1 /ω 2 regardless of the direct and indirect character of the bandgap. The GaAs measurement data agrees well with corresponding theoretical predictions for direct semiconductors. The Si data reveals similar trends albeit with smaller overall absorption strength. In addition, different crystallographic orientations and polarization configurations are analyzed.