Reduction of the Far-Field Divergence Angle of an 850nm Multi-Leaf Holey Vertical Cavity Surface Emitting Laser

By introducing multi-leaf sectorial holes into an oxidation confined 850 nm vertical cavity surface emitting laser (VCSEL), the far-field divergence angle is reduced. The finite-difference time-domain method is used to simulate the far-field pattern of the multi-leaf holey VCSEL with different etching depths and different shapes of the oxide aperture in diameter R. Based on the simulation result, we design and fabricate a multi−leaf holey VCSEL and its divergence angle is only 6°. The experimental results agree well with the theoretical predication.