A Weak-Resonant-Cavity Fabry–Perot Laser Diode With Injection-Locking Mode Number-Dependent Transmission and Noise Performances

Quasi-color-free weak Fabry-Perot cavity laser diode with long cavity length is one alternative solution of the wavelength-division-multiplexed passive optical network (WDM-PON) transmitter with comparable broadband gain spectrum and greatly reduced noise figure as compared to typical reflective semiconductor optical amplifiers. In this paper, the amplified spontaneous emission injection-locked weak-resonant-cavity Fabry-Perot laser diode (WRC-FPLD) with 1% front-facet reflectivity directly modulated at 1.25 Gbit/s with detuning injection-locked mode for quasi-color-free transmission in WDM-PON system with channel spacing of 200 GHz is demonstrated. With bias current changing from 0.9 I_th to 1.4 I_th, the improvement on receiving power sensitivity for the WRC-FPLD-based WDM-PON transmitter is up to 9 dB at bit error rate (BER) of 10^-9. Increasing the injection-locked mode number from 2 to 3 within temperature variation of 6??C effectively promotes the BER from 10^-8 to 10^-10 at receiving power of -27 dBm associated with a decreasing power penalty of -3.2 dB. The WRC-FPLD with more injection-locked modes within one channel exhibits higher extinction ratio at higher operating temperature within one injection-locked-mode-number changing period. This elucidates well the cycling evolution on the BER performance of the WRC-FPLD as a function of operating temperature.