Over 100 GHz 3-dB down bandwidth by direct modulation of a coupled cavity DFB-LD due to photon-photon resonance

摘要

This paper reports on 3-dB down bandwidth of 110.6 GHz by direct modulation of a coupled cavity DFB-LD with phase-shifted/uniform gratings due to photon-photon resonance when the injected current is 3.5 times the threshold current. The photon-photon resonance between the main-mode and sub-mode is analyzed from the viewpoint of threshold gain and detuning between the main-mode and sub-mode. It is found that the detuning between the main-mode and sub-mode contributes to enhancement of the 3-dB down bandwidth.