Diffraction-type surface-emitting semiconductor lasers

Abstract

The present application provides a diffraction-type surface-emitting semiconductor laser. The diffraction-type surface-emitting semiconductor laser includes an upper electrode, an upper cladding layer, an upper waveguide layer, an active layer, a lower waveguide layer, and a lower cladding layer. When carriers are injected into the active layer, the active layer emits light. An optical modulation structure with a radius of R is provided on at least one side of the active layer, and a microcavity with a radius of r is formed in the central region of the optical modulation structure. The optical modulation structure includes a first annular grating structure or a first annular photonic crystal structure. Moreover, the value range of r / R is 4% to 44%. The above-mentioned diffraction-type surface-emitting semiconductor laser can increase the threshold gain difference between the fundamental mode and the higher-order mode by controlling the size of the microcavity and the optical modulation structure to meet the above-mentioned relationship, thereby facilitating the preferential lasing of a single-mode laser with a small divergence angle and a small laser beam quality factor.

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