Compact beam control via non-periodic tantalum pentoxide high contrast gratings in GaN green laser

Abstract

This study demonstrates a gallium nitride (GaN)-based green laser integrated with a non-periodic tantalum pentoxide (Ta2O5) high contrast grating (HCG). By introducing abrupt wavefront phase changes through the HCG, large-angle beam deflection and linear focusing with a specific focal length are achieved. While maintaining high transmittance, the device also exhibits excellent modulation efficiency. Compared with other metasurface works, the non-periodic HCG exhibits significant advantages in both fabrication and integration. This integration method also provides a new solution for miniaturized optical systems.