Wavelength tunable 4-element laser array

Abstract

A wavelength tunable 4-element laser array is fabricated with high performances suitable for the frequency division multiplexing (FDM) system. The array consists of four 1 .55 j.m DFB (distributed feedback) PPIBH (p-substrate partially inverted buried heterostructure) lasers with beam spacing of 125 jim. The lasing wavelength is tuned by changing the ratio of input currents to the two electrodes. The lasing frequency of the array can be allocated with a frequency interval of 10 GHz. An FM efficiency as large as 1 GHz/mA and a flat FM response with variation less than 3 dB in the modulation frequency range from 20 kHz to 1 GHz have been realized. An electrical crosstalk is less than -30 dB up to 800 MHz.