Bragg refractive waveguide edge transmitting semiconductor laser with low horizontal divergence angle

Abstract

The invention relates to a Bragg refractive waveguide edge transmitting semiconductor laser with a low horizontal divergence angle, wherein the P electrode of the laser is placed on the top face of a cover layer and is electrically connected onto the cover layer; the N electrode is positioned on the back face of a substrate and is electrically connected to the substrate; a center cavity is positioned between an upper waveguide layer and a lower waveguide layer; an active area is inserted in the center cavity; a Bragg refractive waveguide formed by periodically distributing a plurality of layers of N-doped materials with a high refractive index and a low refractive index is adopted in the lower waveguide layer on; and a Bragg refractive waveguide formed by periodically distributing a plurality of layers of P-doped materials with a high refractive index and a low refractive index is adopted in the upper waveguide layer. The Bragg refractive waveguide edge transmitting semiconductor laser with the low horizontal divergence angle has the advantages that: effects such as catastrophic damage, hole burning, electric heat overburning, beam filamentization and the like on the end face of the traditional edge transmitting semiconductor laser can be effectively improved, and the laser can realize the large mode-volume and stable single-transverse-mode work because of the great gain loss difference between a basic mode and a high-order mode, the full wave at half maximum (FWHM) of the transverse far-field divergence angle of the laser can reach below 10 DEG.

Description

Technical field: [0001] The invention belongs to the technical field of semiconductor lasers, and relates to a Bragg reflective waveguide edge-emitting semiconductor laser with a low lateral laser beam divergence angle. Background technique: [0002] High-power semiconductor lasers have extremely important applications in laser material processing, pumping, medical treatment, sensing, display technology, frequency conversion, space communication and national defense. With the expansion of application fields, the performance requirements of semiconductor lasers are also increasing. High, such as high output power, stable single-mode characteristics, low far-field divergence angle, high beam quality, etc. [0003] The traditional semiconductor laser structure includes N-face electrode, substrate, buffer layer, lower confinement layer, lower waveguide layer, active region, upper waveguide layer, upper confinement layer, capping layer and P-face electrode from bottom to top; P-f...

AI Technical Summary

Problems solved by technology

However, due to the larger volume of the structured light mode of these lasers, the problem of multi-mode operation is more serious, which will make the far-field pattern complex and the quality of the laser beam will be greatly reduced, so the lateral far-field divergence angle (full width at half maximum FWHM) can only reach more than a dozen degrees, it is difficult to obtain a narrower lateral far-field divergence angle

In addition, these lasers are very sensitive to the small refractive index changes caused by the deviation of the composition of the epitaxial growth structure or the temperature change, and the power, efficiency, and mode of the laser are unstable, so the epitaxial growth, preparation process, and operating current and temperature are demanding.

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