EDGE-EMITTING SEMICONDUCTOR LASER ELEMENT

• US 20140036947A1
• Filed: 02/29/2012
• Published: 02/06/2014
• Est. Priority Date: 03/08/2011
• Status: Active Grant

• Current Assignee: Hamamatsu Photonics KK, Kyoto University
• Original Assignee: Hamamatsu Photonics KK, Kyoto University
• Inventors: Watanabe, Akiyoshi, Hirose, Kazuyoshi, Shibata, Kousuke, Sugiyama, Takahiro, Kurosaka, Yoshitaka, Noda, Susumu
• Granted Patent: US 9,219,348 B2
• Time in Patent Office: Days
• US Class Current: 372/44.01
• CPC Class Codes: H01S 2301/18 Semiconductor lasers with special structural design for influencing the near- or far-field
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: H01S 5/12 the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers comprising a photonic bandgap structure H01S5/11; surface-emitting lasers H01S5/18
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure

Abstract

The present edge-emitting semiconductor layer element includes two-dimensional photonic crystals 4 formed in a semiconductor layer, and when one direction of a contact region of an electrode 8 is provided as a length direction (X-direction) and a direction perpendicular to both of the length direction and a thickness direction of a substrate is provided as a width direction (Y-direction), the two-dimensional photonic crystals 4 are, when viewed from a direction (Z-axis) perpendicular to the substrate, located in a region containing the electrode contact region and wider in the width direction than the contact region, and have a refractive index periodic structure in which the refractive index satisfies a Bragg'"'"'s diffraction condition while periodically changing at every interval along the one direction (X-axis).

Claims

1. An edge-emitting semiconductor laser element comprising:

a semiconductor layer formed by at least an active layer, a light guide layer, and a cladding layer being stacked in sequence on a substrate; and

a drive current electrode being in contact with the semiconductor layer, and a contact region of which with the semiconductor layer extends along one direction perpendicular to a thickness direction of the substrate,

wherein the edge-emitting semiconductor laser element emits laser light from an edge located at one end in the one direction in the active layer,

wherein said edge-emitting semiconductor laser element further comprises a two-dimensional photonic crystal formed in the semiconductor layer,

wherein the one direction of the contact region defined as a length direction and a direction perpendicular to both of the length direction and the substrate thickness direction is defined as a width direction,

wherein when viewed from a direction perpendicular to the substrate, the two-dimensional photonic crystal is located in a region containing the contact region and wider in the width direction than the contact region,.

wherein the two-dimensional photonic crystal comprises a refractive index periodic structure in which the refractive index periodically changes at every interval d1 along the one direction,

wherein the two-dimensional photonic crystal satisfies a Bragg'"'"'s diffraction condition;

d1=q1×

λ

/(2×

n)

with respect to the laser light with a wavelength of λ

, where q1 is a natural number and n is an effective refractive index of light in the active layer.

2. The edge-emitting semiconductor laser element according to claim 1, wherein

the two-dimensional photonic crystal

has a refractive index periodic structure in which the refractive index periodically changes at every interval d2 along a direction that intersects the one direction, and

satisfies a Bragg'"'"'s diffraction condition:

d2=q2×

λ

/(2×

n)

with respect to the laser light with a wavelength of λ

, where q2 is a natural number.

3. The edge-emitting semiconductor laser element according to claim 1,

wherein supplied carries are spread out by some sizes from both end positions of the contact region in the width direction;

and

wherein when viewed from a direction perpendicular to the substrate, the two-dimensional photonic crystal is located in a region equal to or wider in the width direction than a region, and this region includes the contact region and is wider than the contact region by the carrier-spread-out sizes in the width direction.

4. The edge-emitting semiconductor laser element according to claim 3, wherein the dimension is 3 μ

m.

5. The edge-emitting semiconductor laser element according to claim 1,

wherein generated light in the active layer is seeped out by some sizes from both end positions of the contact region in the width direction;

and

wherein when viewed from a direction perpendicular to the substrate, the two-dimensional photonic crystal is located in a region equal to or wider in the width direction than a region, and this region includes the contact region and is wider than the contact region by the light-seeped-out sizes in the width direction.