1.3- m In(Ga)As Quantum-Dot VCSELs Fabricated by Dielectric-Free Approach With Surface-Relief Process

摘要

We present the 1.3-$mu$ m In(Ga)As quantum-dot (QD) vertical-cavity surface-emitting lasers (VCSELs) fabricated by the dielectric-free (DF) approach with the surface-relief (SR) process. Compared with the conventional dielectric-dependent (DD) method, the lower differential resistance and improved output power have been achieved by the DF approach. With the same oxide aperture area, the differential resistance is reduced by 36.47% and output power is improved by 78.32% under continuous-wave operation; it is up to 3.42 mW under pulsed operation with oxide aperture diameter $sim$15 $mu$m. The surface-relief technique is also applied, for the first time, in 1.3- $mu$m QD VCSELs, and it effectively enhances the emission of the fundamental mode. The characteristic of small signal modulation response is also analyzed.