Lateral loss effects on modulation bandwidth in VCSELs

Abstract

Intensity noise and chromatic fiber dispersion in analog optical communication systems are attributed to harmonic and inter-modulation distortion in the amplitude modulation of semiconductor lasers. In addition, maximum usable bandwidth of the communication systems is limited by harmonic distortion. Due to the use of Fabry Perot type resonator, second harmonic distortion exists in both edge-emitting devices and VCSELs. However the distortion caused by lateral loss may be more so in VCSELs because of its smaller core size. Two factors, namely, the lateral field confinement factor and the lateral loss due to diffraction, are considered for their effect on harmonic distortion when the laser device is under small signal modulation.published_or_final_versio