Four‐channel directly modulated square‐rectangular laser array in the O‐band.

A four‐channel directly modulated square‐rectangular laser array was demonstrated in 1.3 μm wavelength range with the wavelength interval about 5 nm. The laser array shows stable single mode operation with the side‐mode suppression ratio (SMSR) over 30 dB, 3‐dB modulation bandwidth above 11.8 GHz and an open‐eye diagram is obtained at data rates of 10 Gb/s, and the relative intensity noise (RIN) about −138 dB/Hz up to 5 GHz for all channels. [ABSTRACT FROM AUTHOR]