An equivalent-stepped-index-coupled DFB semiconductor laser and laser array realized by stepping the duty cycle of the Sampled Bragg grating

Abstract

An equivalent-stepped-index-coupled (ESIC) distributed feedback semiconductor laser with an equivalent-stepped duty cycle (ESDC) is proposed and investigated numerically. The ESDC grating profile is realized by stepping the duty cycle of a Sampled Bragg grating (SBG) with the uniform seeding grating. Numerical results show that the light will be distributed in larger region along the laser cavity , that is to say, light field will be flattened and spatial hole burning can be suppressed in such flexible structure. Based on the ESDC structure, different sampling structures in a DFB laser array can also be obtained by stepping the sampling periods; therefore, multi-wavelength laser array can be designed and fabricated, which would simplify the fabrication process , and may be more suitable for the high precision and massive fabrication of DFB laser and laser array with reduced spatial hole burning. • We proposed an equivalent-stepped-duty cycle (ESDC) grating structure. • The ESDC profile is realized by stepping the duty cycle of a Sampled Bragg grating. • An equivalent-stepped-index-coupled (ESIC) DFB laser is based on the ESDC grating. • The SHB is suppressed effectively in the ESIC DFB laser. • The ESIC DFB laser array can be designed and fabricated easily based on the REC.