External optical modulator using a low-cost Fabry-Perot laser diode for optical access networks

We propose and demonstrate an external optical modulation method based on TE/TM-mode absorption nulls in a Multiple Quantum Well (MQW) Fabry-Perot laser diode (FP-LD). The center wavelength of the absorption nulls is rapidly shifted to short-wavelength by the small current change (similar to1 mA) in the FP-LD, which can modulate optical signal with more than 10 dB of extinction ratio (ER). The shift of the center wavelength comes from the refractive index change due to anomalous dispersion and plasma effect in MQW FP-LD waveguide. Non-inverting and inverting signals are made by TE- and TM-mode absorption nulls at 155.52 Mbps and BERs for the signals are measured, respectively.