Optical active device

• US 20040062505A1
• Filed: 03/06/2003
• Published: 04/01/2004
• Est. Priority Date: 09/26/2002
• Status: Active Grant

• Current Assignee: Kyoto University, Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Kyoto University, Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Noda, Susumu, Sugitatsu, Atsushi
• Granted Patent: US 7,181,120 B2
• Time in Patent Office: Days
• US Class Current: 385/131
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 6/1225 comprising photonic band-gap structures or photonic lattices

Abstract

In an optical device a slab layer has a configuration such that an active layer is sandwiched between two cladding layers. Periodic air hole structures are formed in the slab layer. A linear defect region is provided in a part of the air hole structures. As a result, laser oscillation is generated at the band end in the two-dimensional photonic crystal waveguide mode.

Claims

1. An optical active device comprising a two-dimensional slab photonic crystal structure, in which a slab layer having two-dimensional expanse and formed by laminating an active layer and a cladding layer, has a periodic refractive-index distribution structure in a two-dimensional plane,

wherein the slab layer has a waveguide formed by introducing a first linear defect region in the periodic refractive-index distribution structure.

2. The optical active device according to claim 1, wherein one end in the longitudinal direction of the first linear defect region is terminated by the periodic refractive-index distribution structure in the slab layered plane.

3. The optical active device according to claim 1, wherein both ends in the longitudinal direction of the first linear defect region are terminated by the periodic refractive-index distribution structure in the slab layered plane.

4. The optical active device according to claim 1, wherein the active layer is formed only in a portion where the first linear defect region is introduced.

5. The optical active device according to claim 1, wherein a point defect or an isolated defect is further introduced in the periodic refractive-index distribution structure.

6. The optical active device according to claim 5, wherein the point defects or isolated defects are formed in plurality.

7. The optical active device according to claim 5, further comprising a control unit that can control the refractive index of the point defect or isolated defect independently of the first linear defect region.

8. The optical active device according to claim 5, further comprising a control unit that can control the refractive index in a region near the point defect or isolated defect.

9. The optical active device according to claim 1, wherein a second linear defect region is further introduced in the periodic refractive-index distribution structure.

10. The optical active device according to claim 1, wherein a second linear defect region is further introduced in the periodic refractive-index distribution structure, and a control unit that can control the refractive index of the second linear defect region, independently of the first linear defect region, is further provided.

11. The optical active device according to claim 5, wherein the active layer is formed only in a portion where the first linear defect region and the point defect or isolated defect are introduced, and a control unit that can control the refractive index of the point defect or isolated defect, independently of the first linear defect region, is further provided.

12. The optical active device according to claim 5, further comprising a control unit that can control the refractive index of a region between the first linear defect region and the point defect or isolated defect.

13. The optical active device according to claim 5, wherein the active layer is formed only in a portion where the first linear defect region is introduced, and a portion between the first linear defect region and the point defect or isolated defect.

14. The optical active device according to claim 5, further comprising:

an optical monitoring unit that monitors light emitted from the point defect or the isolated defect; and

an optical property control unit that controls optical properties of the optical active device, based on the monitored light.

15. The optical active device according to claim 1, further comprising a control unit that can control the refractive index of the first linear defect region.

16. The optical active device according to claim 1, wherein the active layer is formed in a portion excluding the portion where the first linear defect region is introduced.

17. The optical active device according to claim 1, wherein a second linear defect region extending substantially parallel with the first linear defect region, two first point defects or isolated defects interacting with the second linear defect region, and a second point defect or isolated defect interacting with the first and second linear defect regions are introduced in the periodic refractive-index distribution structure, a master oscillator is formed of the second linear defect region having a resonance frequency fixed by the first point defects or isolated defects, and a slave power amplifier which amplifies the light from the master oscillator introduced from the second point defect or isolated defect is formed of the first linear defect region.

18. The optical active device according to claim 1, wherein the first linear defect region parallel-displaces one of the periodic refractive-index distribution structures in a direction perpendicular to the first linear defect region in the slab layered plane, to thereby change the width of the first linear defect region.