PHOTONIC CRYSTAL SURFACE EMITTING LASER

• US 20110158280A1
• Filed: 04/08/2010
• Published: 06/30/2011
• Est. Priority Date: 05/07/2009
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Uchida, Takeshi, Nagatomo, Yasuhiro
• Granted Patent: US 8,416,826 B2
• Time in Patent Office: Days
• US Class Current: 372/50.1
• CPC Class Codes: H01S 5/1039 Details on the cavity length
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: H01S 5/18319 comprising a periodical structure in lateral directions
• CPC Class Codes: H01S 5/2027 Reflecting region or layer, parallel to the active layer, e.g. to modify propagation of the mode in the laser or to influence transverse modes

Abstract

The present invention provides a photonic crystal surface emitting laser with which an arbitrary beam shape can be obtained and which enables design with a high degree of freedom. The surface emitting laser including a photonic crystal having a resonance mode in an in-plane direction parallel to a substrate includes a reflecting mirror for reflecting light emitted from the photonic crystal in a normal direction of the substrate and a spacer layer interposed between the reflecting mirror and the photonic crystal, wherein a nonuniform in-plane distribution is provided to the characteristics of one of the reflecting mirror and the spacer layer, so that a Q-value, which is a resonator characteristic in the normal direction of the substrate in the surface emitting laser, has a nonuniform in-plane distribution.

Claims

1. A photonic crystal surface emitting laser comprising:

a photonic crystal having a resonance mode in an in-plane direction of a substrate;

an active layer located in the vicinity of the photonic crystal and caused to emit light by carrier injection;

a reflecting mirror for reflecting light emitted from the photonic crystal in a normal direction of the substrate; and

a spacer layer interposed between the reflecting mirror and the photonic crystal,

wherein one of the reflecting mirror and the spacer layer is composed so that a Q-value, which is a resonator characteristic in the normal direction of the substrate, has a nonuniform in-plane distribution.

2. The photonic crystal surface emitting laser according to claim 1, wherein a complex amplitude of reflected light reflected by the reflecting mirror to make a round trip in the spacer layer has a nonuniform in-plane distribution.

3. The photonic crystal surface emitting laser according to claim 2, wherein an intensity of the reflected light has a nonuniform in-plane distribution.

4. The photonic crystal surface emitting laser according to claim 3, wherein a reflectance of the reflecting mirror has a nonuniform in-plane distribution.

5. The photonic crystal surface emitting laser according to claim 3, wherein a light absorption coefficient of the spacer layer has a nonuniform in-plane distribution.

6. The photonic crystal surface emitting laser according to claim 2, wherein a phase of the reflected light has a nonuniform in-plane distribution.

7. The photonic crystal surface emitting laser according to claim 6, wherein a thickness of the spacer layer has a nonuniform in-plane distribution.

8. The photonic crystal surface emitting laser according to claim 6, wherein an average refractive index of the spacer layer has a nonuniform in-plane distribution.

9. The photonic crystal surface emitting laser according to claim 1, wherein a nonuniform in-plane distribution of characteristics of one of the reflecting mirror and the spacer layer is variable.

10. The photonic crystal surface emitting laser according to claim 1, wherein the photonic crystal is two-dimensionally disposed in an array within a plane.