Single-mode VCSELs utilizing annular metal apertures for lateral confinement and on-chip beam shaping techniques

To ensure high-beam-quality single-mode operation of vertical-cavity surface-emitting lasers across diverse temperatures, we propose a surface-microstructured device combining annular metal-dielectric multilayers and an on-chip optical microlens feedback cavity.This architecture effectively suppresses thermally induced mode hopping and side-mode degradation. Using a wafer-level integration process, Ti/Pt multilayers confine transverse modes, while a SiO₂/Ti₃O₅ microlens enhances optical feedback. The device achieves a single-mode output of 4.1 mW at 0 °C (driven by 8.5 mA), with side-mode suppression ratios exceeding 25 dB across 0-80 °C and 40.6 dB at 40 °C (8 mA). This monolithic strategy ensures thermal stability without the use of external optics, reducing package volume compared with hybrid solutions.