Surface emitting laser

• US 7,733,936 B2
• Filed: 04/24/2006
• Issued: 06/08/2010
• Est. Priority Date: 04/28/2005
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Okamoto, Kohei
• Primary Examiner(s): Harvey; Minsun
• Assistant Examiner(s): Park; Kinam
• Application Number:
  US11/409,022
• Publication Number:
  US 20070121694A1
• Time in Patent Office: 1,506 Days
• Field of Search: 372/50.124, 372/43.01, 372/50.11, 372/99
• US Class Current: 372/50.124
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/0604 comprising a non-linear region, e.g. generating harmonics of the laser frequency
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: H01S 5/1225 with a varying coupling constant along the optical axis
• CPC Class Codes: H01S 5/1228 DFB lasers with a complex coupled grating, e.g. gain or loss coupling
• CPC Class Codes: H01S 5/183 having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL]
• CPC Class Codes: H01S 5/18358 containing spacer layers to adjust the phase of the light wave in the cavity
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser
• CPC Class Codes: H01S 5/34366 based on InGa(Al)AS

Abstract

There is provided a novel surface emitting laser structure unnecessary to have multilayer mirrors in both of upper and lower sides of an active layer. A surface emitting laser comprises a two-dimensional periodic structure which is comprised of an active material having a gain in a specific wavelength band of electromagnetic waves, and a reflecting mirror arranged apart by a predetermined distance so as to face the above-mentioned two-dimensional periodic structure, and these are comprised so as to make laser oscillation possible. At that time, the above-mentioned two-dimensional periodic structure is formed of a two-dimensional photonic crystal which is comprised of a dielectric, and a resonator is comprised of a reflecting mirror pair formed by combination with the above-mentioned reflecting mirror to make laser oscillation generated.

Claims

1. A vertical resonator type surface emitting laser, comprising:

a first reflecting mirror;

a first active layer, in which a refractive index in an in-plane direction of the first active layer changes periodically so that the first active layer serves as a second reflecting mirror provided oppositely to the first reflecting mirror, wherein the first active layer comprises a high resistance region and a low resistance region of a lower resistance than the high resistance region;

a second active layer provided between the first reflecting mirror and the second reflecting mirror, any refractive index of which does not change periodically;

a first spacer layer provided between the first reflecting mirror and the second active layer; and

a second spacer layer provided between the second active layer and the second reflecting mirror,

wherein the first and second reflecting mirrors contribute to a vertical resonator function of the vertical resonator type surface emitting layer.

2. The vertical resonator type surface emitting laser according to claim 1, wherein an emission window for emitting laser light to an external area is provided in a two-dimensional periodic structure of the first active layer.

3. The vertical resonator type surface emitting laser according to claim 1, wherein a two-dimensional periodic structure of the first active layer has a defect that disturbs a periodicity of the two-dimensional periodic structure.

4. The vertical resonator type surface emitting laser according to claim 1, wherein the first reflecting mirror includes a dielectric multilayer film.

5. The vertical resonator type surface emitting laser according to claim 1, wherein the first reflecting mirror, or a region between the first active layer and the first reflecting mirror, includes a nonlinear optical material.

6. The vertical resonator type surface emitting laser according to claim 1, wherein the first active layer includes means making a gain distribution.