The influence ot oxidation aperture on the output characteristics ot the circularly symmetric vertical-cavity-surtaceemitting laser(VCSEL) structure is investigated.To do so,VCSELs with different oxide aperture sizes ...The influence ot oxidation aperture on the output characteristics ot the circularly symmetric vertical-cavity-surtaceemitting laser(VCSEL) structure is investigated.To do so,VCSELs with different oxide aperture sizes are simulated by the finite-difference time-domain(FDTD) method.The relationships among the field distribution of mode superposition,mode wavelength,output spectra,and far-field divergence with different oxide apertures are obtained.Further,VCSELs respectively with oxide aperture sizes of 2.7 μm,4.4 μm,5.9 μm,7 μm,8 μm,9 μm,and 18.7 μm are fabricated and characterized.The maximum output power increases from 2.4 mW to 5.7 mW with oxide aperture increasing from 5.9 μm to 9 μm.Meanwhile,the wavelength tuning rate decreases from 0.93 nm/mA to 0.375 nm/mA when the oxide aperture increases from 2.7 μm to 9 μm.The thermal resistance decreases from 2.815℃/mW to 1.015℃/mW when the oxide aperture increases from 4.4 μm to 18.7μm.It is demonstrated theoretically and experimentally that the wavelength spacing between adjacent modes increases with the augment of the injection current and the spacing becomes smaller with the oxide aperture increasing.Thus it can be reported that the aperture size can effectively reduce the mode overlaying but at the cost of the power decreasing and the wavelength tuning rate and thermal resistance increasing.展开更多
Optical gain and thermal carrier loss distributions regarding current diffusion and various electric contact areas are investigated to improve the near-field modes from the ring-shape to a Gaussian-like configuration ...Optical gain and thermal carrier loss distributions regarding current diffusion and various electric contact areas are investigated to improve the near-field modes from the ring-shape to a Gaussian-like configuration for extra-broad-area and oxide-confined vertical-cavity surface-emitting lasers. In this work an equivalent circuit network model is used. The resistance of the continuously-graded distributed Bragg reflectors (DBRs), the current diffusion and the temperature effect due to different electric-contact areas are calculated and analyzed at first, as these parameters affect one another and are the key factors in determining the gain and thermal carrier loss. Finally, the gain and thermal carrier loss distributions are calculated and discussed.展开更多
文摘The influence ot oxidation aperture on the output characteristics ot the circularly symmetric vertical-cavity-surtaceemitting laser(VCSEL) structure is investigated.To do so,VCSELs with different oxide aperture sizes are simulated by the finite-difference time-domain(FDTD) method.The relationships among the field distribution of mode superposition,mode wavelength,output spectra,and far-field divergence with different oxide apertures are obtained.Further,VCSELs respectively with oxide aperture sizes of 2.7 μm,4.4 μm,5.9 μm,7 μm,8 μm,9 μm,and 18.7 μm are fabricated and characterized.The maximum output power increases from 2.4 mW to 5.7 mW with oxide aperture increasing from 5.9 μm to 9 μm.Meanwhile,the wavelength tuning rate decreases from 0.93 nm/mA to 0.375 nm/mA when the oxide aperture increases from 2.7 μm to 9 μm.The thermal resistance decreases from 2.815℃/mW to 1.015℃/mW when the oxide aperture increases from 4.4 μm to 18.7μm.It is demonstrated theoretically and experimentally that the wavelength spacing between adjacent modes increases with the augment of the injection current and the spacing becomes smaller with the oxide aperture increasing.Thus it can be reported that the aperture size can effectively reduce the mode overlaying but at the cost of the power decreasing and the wavelength tuning rate and thermal resistance increasing.
基金Project supported by the National Natural Science Foundation of China(Grant No.10974012)
文摘Optical gain and thermal carrier loss distributions regarding current diffusion and various electric contact areas are investigated to improve the near-field modes from the ring-shape to a Gaussian-like configuration for extra-broad-area and oxide-confined vertical-cavity surface-emitting lasers. In this work an equivalent circuit network model is used. The resistance of the continuously-graded distributed Bragg reflectors (DBRs), the current diffusion and the temperature effect due to different electric-contact areas are calculated and analyzed at first, as these parameters affect one another and are the key factors in determining the gain and thermal carrier loss. Finally, the gain and thermal carrier loss distributions are calculated and discussed.