Vol. 56, Issue 1, pp. 75-88 (2026)

Abstract

The self-heating effect of multi-junction vertical cavity surface emitting lasers (MJ VCSELs) under continuous current injection seriously affects their output performance and durability. In this study, we designed and simulated a multi-junction bottom-emitting VCSEL structure. By adopting the n-type oxide layers and the component gradient spacer layers, the optical output performance of the device under continuous current injection was effectively improved. Compared with the traditional MJ VCSEL structure, the designed device can achieve a peak power increase of more than 30 mW and an 18% improvement in electro-optical power conversion efficiency (PCE) without changing the oxidation aperture. Meanwhile, this new type of MJ VCSEL shows good adaptability to the increase of environmental temperature. Even at an ambient temperature of 80 ℃, it can still achieve comparable performance to the traditional structure of MJ VCSEL at room temperature. The results of this study indicate that the structure we designed is promising for the achievement of high-performance MJ VCSELs.