VERTICAL CAVITY SURFACE EMITTING LASER AND METHOD OF MANUFACTURING TWO-DIMENSIONAL PHOTONIC CRYSTAL OF VERTICAL CAVITY SURFACE EMITTING LASER

Abstract

A vertical cavity surface emitting laser includes an active layer between a first reflector and a second reflector and at least either the first reflector or the second reflector includes a two-dimensional photonic crystal. The two-dimensional photonic crystal has a structure 106 showing an ununiform effective refractive index distribution in the plane of the reflector to realize both a high reflectivity and transverse mode control at the same time.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of the vertical cavity surface emitting laser of Example 1, illustrating the configuration thereof.

FIG. 2 is a schematic illustration of the vertical cavity surface emitting laser of Example 2, illustrating the configuration thereof.

FIG. 3 is a schematic illustration of the vertical cavity surface emitting laser of Example 3, illustrating the configuration thereof.

FIG. 4 is a schematic illustration of the vertical cavity surface emitting laser of Example 4, illustrating the configuration thereof.

FIG. 5 is a schematic illustration of the vertical cavity surface emitting laser of Example 5, illustrating the configuration thereof.

Claims

1. A vertical cavity surface emitting laser comprising an active layer between a first reflector and a second reflector; at least either the first reflector or the second reflector including a two-dimensional photonic crystal;the reflector including the two-dimensional photonic crystal having a structure showing an ununiform effective refractive index distribution in the plane of the reflector.

2. The laser according to claim 1, wherein the structure realizing the ununiform effective refractive index distribution is formed by modulating the depth of holes formed in the two-dimensional photonic crystal for transverse mode control.

3. The laser according to claim 2, wherein the depth of the holes is modulated by arranging a filler in the holes of the two-dimensional photonic crystal.

4. The laser according to claim 2, wherein the depth of the holes is modulated in a Gaussian form or modulated to make the depth proportional to the distance from or the square of the distance from a center.

5. The laser according to claim 1, wherein the structure realizing the ununiform effective refractive index distribution is formed by ununiformly changing the density of the holes of the two-dimensional photonic crystal.

6. The laser according to claim 1, wherein the two-dimensional photonic crystal is formed in a distributed Bragg reflector constituting the reflectors of the vertical cavity surface emitting laser.

7. A method of manufacturing a two-dimensional photonic crystal of the vertical cavity surface emitting laser according to claim 1, the method comprising: forming holes showing an ununiform distribution of depth in the two-dimensional photonic crystal.

8. The method according to claim 7, wherein the holes showing an ununiform distribution of depth are formed by dry etching so as to show a pattern of hole diameters increasing as a function of the distance from a center of the two-dimensional photonic crystal.

9. The method according to claim 7, wherein the ununiform distribution of depth is formed by arranging a filler in the holes of the two-dimensional photonic crystal.

10. The method according to claim 7, wherein the ununiform distribution of depth is formed to show a Gaussian distribution profile or to make the depth proportional to the distance from or the square of the distance from the center.

11. A vertical cavity surface emitting laser comprising a first reflector, a second reflector and an active layer interposed between the reflectors arranged on a substrate; at least either the first reflector or the second reflector having a two-dimensional photonic crystal structure;the two-dimensional photonic crystal structure showing a refractive index pattern diminishing from the center portion of a light emitting region toward the outer periphery thereof.