Open AccessSeparation of coherent and incoherent nonlinearities in a heterodyne pump-probe experiment
Author(s) -
Paola Borri,
F. Romstad,
Wolfgang Werner Langbein,
Anthony E. Kelly,
Jesper Mørk,
Jørn Märcher Hvam
Publication year - 2000
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.7.000107
Subject(s) - optics , heterodyne detection , heterodyne (poetry) , physics , transient (computer programming) , four wave mixing , optical amplifier , nonlinear optics , amplifier , signal (programming language) , laser , optoelectronics , acoustics , computer science , cmos , programming language , operating system
We demonstrate that the transient coherent nonlinearity (coherent artifact) affecting the pump-probe response of semiconductor optical amplifiers can be experimentally separated from the incoherent transient. The technique is based on measuring the mirror component of the coherent artifact which is a background-free four--wave mixing signal at a different frequency with respect to the transmitted probe in a heterodyne detection scheme. Measurements on amplifiers of different length reveal strong deviations from the commonly expected symmetric shape of the coherent artifact in case of long waveguides.