Comparison of coupling characteristics for several spotsize-converter-integrated laser diodes in the 1.3-μm-wavelength region

Four types of spotsize-converter-integrated laser diodes (SS-LDs) are numerically compared from the viewpoint of the coupling characteristics to the single-mode fiber in the 1.3-μm-wavelength region. The comparison is based on the semivectorial three-dimensional (3-D) finite-difference (FD) beam propagation method (BPM). The SS-LDs investigated here are categorized into a group with vertical tapers and a group with a combination of a lateral taper and a thin-film core. The features of the SS-LDs are clarified.