Sichuan University achieves breakthrough in VCSEL laser conversion efficiency to promote the development of autonomous driving lidar

Since its introduction, edge-emitting laser (EEL) technology has continued to break records for power conversion efficiency (PCE), reaching a record high of 85% at an operating temperature of -50°C in 2006. Subsequently, in 2007, EEL technology reached a high conversion efficiency of 76% at room temperature. However, no new efficiency records have been set in the 15 years since then, and the above efficiency is the highest efficiency that semiconductor lasers can achieve.

In contrast, the efficiency of vertical cavity surface emitting lasers (VCSELs) has been increasing at a slower pace. Since its maximum PCE efficiency reached 62% in 2009, no major breakthroughs have been achieved, so there is a clear performance gap between VCSEL and EEL technologies. As a micro-cavity surface laser, achieving high-efficiency conversion in the photon field has always been a challenge for VCSELs.

Due to its low power and efficiency, VCSEL's early applications were mainly focused on small, low-power consumer electronics and short-range communications in data centers. In recent years, with the advancement of smart technology, low-power VCSEL has become a key core light source chip for smart sensing systems, and has been widely used in fields such as face recognition and short-range sensing, with remarkable success.

In recent years, with the rapid development of artificial intelligence technology, the application potential of VCSEL in sensing, communication, atomic clock, optical/quantum computing, topological laser and medical diagnosis has become increasingly apparent. In particular, the increasing demand for remote sensing technology in autonomous driving, the need for AI computing power in high-speed data processing centers, and the growth in the number of VCSELs in intelligent and quantum technology applications have highlighted the importance of energy consumption, a core issue, to VCSELs.

The energy efficiency of VCSEL has a significant impact on the energy consumption of mobile devices and data centers. Therefore, the research and development of ultra-high-efficiency VCSEL is crucial to supporting the development of terminal devices in the future intelligent era and also plays an important role in promoting the development of green energy photonics.