Characteristics Improvement of Surface-Emitting Distributed Feedback Lasers With ITO Claddings

In this study, significant improvements in the characteristics of the InAs quantum-dot surface-emitting distributed feedback lasers using indium tin oxide as a cladding material covered by two types of newly designed metal contacts were achieved. Laser characteristics at room temperature including I-V curves, L-I curves, near-field patterns, and lasing spectra are analyzed and discussed. We adopted a metal grating and a metal strip as p-type electrodes to improve the current distribution of the devices. Uniform laser emission in the near-field was observed. Moreover, substantial reductions in the ohmic resistance of 9.35 Ω and a low-threshold current density of 0.28 kA/cm
²
were both achieved under continuous-wave operation, leading to the prospect of high-performance surface emitting distributed feedback.