Presentation Information
[8p-N301-19]Effect of aperture on laser characteristics of GaN-based vertical-cavity surface-emitting lasers
〇Naoki Shibahara1, Shoki Arakawa1, Atsunori Tokushi1, Taiki Kitamura1, Satoshi Kamiyama1, Motoaki Iwaya1, Tetsuya Takeuchi1 (1.Meijo Univ.)
Keywords:
VCSEL,aperture,WPE
To improve the efficiency of GaN-based VCSELs, we fabricated devices with apertures of 3–5 µm and evaluated their wall-plug efficiency (WPE). Under continuous-wave operation at room temperature, the 4 µm device achieved the highest WPE of 27%. As the aperture decreased, threshold current was reduced—1.0 mA for 5 µm, 0.7 mA for 4 µm, and 0.4 mA for 3 µm—indicating thermal advantages of miniaturization. However, the 3 µm device showed increased operating voltage and reduced slope efficiency, leading to a lower WPE of 17%. These results demonstrate that while reducing aperture improves certain characteristics, excessive miniaturization can degrade efficiency due to electrical and optical losses. Therefore, optimizing aperture is essential for achieving high WPE. We plan to further investigate the origin of the high WPE observed in the 4 µm device through detailed analysis of optical losses and thermal resistance, aiming for further performance enhancement.