Electro-absorption modulator integrated with a vertical cavity surface emitting laser

• US 20070002917A1
• Filed: 06/30/2005
• Published: 01/04/2007
• Est. Priority Date: 06/30/2005
• Status: Active Grant

• Current Assignee: II-VI Delaware, Inc. (Coherent Corp.)
• Original Assignee: Finisar Corporation (II-VI Incorporated)
• Inventors: Deng, Hongyu
• Granted Patent: US 7,983,572 B2
• Time in Patent Office: Days
• US Class Current: 372/50.110
• CPC Class Codes: H01S 5/02469 Passive cooling, e.g. where heat is removed by the housing as a whole or by a heat pipe without any active cooling element like a TEC
• CPC Class Codes: H01S 5/04254 characterised by the shape
• CPC Class Codes: H01S 5/18302 comprising an integrated optical modulator
• CPC Class Codes: H01S 5/18308 having a special structure for lateral current or light confinement
• CPC Class Codes: H01S 5/18311 using selective oxidation
• CPC Class Codes: H01S 5/18344 characterized by the mesa, e.g. dimensions or shape of the mesa
• CPC Class Codes: H01S 5/3095 Tunnel junction

Abstract

An electro-absorption modulator integrated with a vertical cavity surface emitting laser (VCSEL). An electro-absorption modulator (EAM) is integrated or grown on a VCSEL. The electro-absorption modulator may be separated from the VCSEL by a semi-insulating or nonconducting layer. Contacts on the EAM can bias the EAM such that light emitted by the VCSEL is selectively absorbed. Thus, the VCSEL can emit a constant wave light that is modulated by the integrated EAM.

Claims

1. A vertical cavity surface emitting device comprising:

a vertical cavity surface emitting section; and

an electro-absorption section integrated with the vertical cavity surface emitting section, the electro-absorption section comprising;

n-type cladding layer;

p-type cladding layer; and

absorption region formed between the n-type cladding layer and the p-type cladding layer, wherein the absorption region selectively absorbs light emitted by the vertical cavity surface emitting section to modulate the light.

2. The device of claim 1, the electro-absorption section being monolithically formed with the vertical cavity surface emitting section.

3. The device of claim 1, wherein the electro-absorption section has a bandedge that is blue shifted relative to a bandedge of the vertical cavity surface emitting section.

4. The device of claim 1, wherein the bandedge of the electro-absorption section is blue-shifted in a range from 10 nanometers to 150 nanometers.

5. The device of claim 1, wherein the bandedge of the electro-absorption section is blue-shifted in a range from 10 to 100 nanometers when the vertical cavity surface emitting lasers lases at about 1310 nanometers or at 1550 nanometers.

6. The device of claim 1, wherein the vertical cavity surface emitting section further comprises:

a bottom mirror;

a top mirror; and

an active region formed between the bottom mirror and the top mirror.

7. The device of claim 6, wherein the bottom mirror and the top mirror each comprise distributed Bragg reflector layers.

8. The device of claim 1, wherein the electro-absorption section further comprises a semi-insulating region that separates the electro-absorption section from the vertical cavity surface emitting section.

9. The device of claim 8, wherein the electro-absorption section further comprises a top contact and a bottom contact used to bias the absorption region such that light emitted by the vertical cavity surface emitting section is modulated.

10. The device of claim 1, wherein the electro-absorption section further comprises a pair of DBR mirrors that sandwich at least the absorption region.

11. The device of claim 1, wherein the vertical cavity surface emitting section is a constant wave light source.

12. The device of claim 1 wherein the electro-absorption section configured for at least one of an InP or GaAs based vertical cavity surface emitting section.

17. A vertical cavity surface emitting laser as defined in claim 11, wherein the EAM further comprises a p contact and an n contact, the p contact and the n contact enabling a voltage to be applied across the EAM.

18. A vertical cavity surface emitting laser as defined in claim 17, wherein the absorption region selectively absorbs light emitted by the vertical cavity surface emitting section such that the light is modulated based on the voltage applied across the EAM.

13. A vertical cavity surface emitting laser comprising:

a vertical cavity surface emitting section comprising;

first distributed Bragg reflector (DBR) mirror;

second DBR mirror; and

active region sandwiched by the first DBR mirror and the second DBR mirror; and

an electro-absorption modulator (EAM) monolithically integrated with the vertical cavity surface emitting section, the EAM comprising;

absorption region sandwiched by a first cladding layer and a second cladding layer, wherein a bandedge of the absorption region is blue-shifted relative to a bandedge of the active region of the vertical cavity surface emitting section; and

third DBR mirror and a fourth DBR mirror that form a cavity that includes the absorption region.

14. A vertical cavity surface emitting laser as defined in claim 13, the EAM further comprising a semi-insulating layer that separates the EAM from the vertical cavity surface emitting section.

15. A vertical cavity surface emitting laser as defined in claim 14, wherein the semi-insulating layer is doped.

16. A vertical cavity surface emitting laser as defined in claim 15, wherein the semi-insulating layer is doped with iron.

19. A vertical cavity surface emitting laser as defined in claim 13, wherein the vertical cavity surface emitting section is a constant light wave source.

20. A vertical cavity surface emitting laser as defined in claim 13, wherein the absorption region is a block material.

21. A vertical cavity surface emitting laser as defined in claim 13, wherein the active region of the surface emitting laser section includes at least one of quantum wells or quantum dots.

22. A vertical cavity surface emitting laser as defined in claim 13, wherein the EAM is configured for at least one of an InP or GaAs based vertical cavity surface emitting section.