Fast injection optical switch

• US 7,989,841 B1
• Filed: 07/31/2007
• Issued: 08/02/2011
• Est. Priority Date: 07/31/2007
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Wang, Shih-Yuan, Kamins, Theodore I., Bratkovski, Alexandre M.
• Primary Examiner(s): Andújar; Leonardo
• Assistant Examiner(s): HARRISTON, WILLIAM A
• Application Number:
  US11/831,704
• Time in Patent Office: 1,463 Days
• Field of Search: 257/107, 257/113, 257/115
• US Class Current: 257/107
• CPC Class Codes: H01L 31/1113 the device being a photothyristor

Abstract

A fast injection optical switch is disclosed. The optical switch includes a thyristor having a plurality of layers including an outer doped layer and a switching layer. An area of the thyristor is configured to receive a light beam to be directed through at least one of the plurality of layers and exit the thyristor at a predetermined angle. At least two electrodes are coupled to the thyristor and configured to enable a voltage to be applied to facilitate carriers from the outer doped layer to be directed to the switching layer. Sufficient carriers can be directed to the switching layer to provide a change in refractive index of the switching layer to redirect at least a portion of the light beam to exit the thyristor at a deflection angle different from the predetermined angle.

Claims

1. A fast injection optical switch, comprising:

a thyristor including a plurality of semiconducting layers having alternating positive and negative conductivity types, wherein the plurality of semiconducting layers includes a outer doped layer and a switching layer;

an area of the thyristor configured to receive a light beam to be directed through at least one of the plurality of semiconducting layers and exit the thyristor at a predetermined angle; and

at least two electrodes coupled to the thyristor and configured to enable a voltage to be applied to facilitate carriers from the outer doped layer to be directed to the switching layer, wherein sufficient carriers are directed to the switching layer to provide a change in refractive index of the switching layer to redirect at least a portion of the light beam to exit the thyristor at a deflection angle different than the predetermined angle.

2. An optical switch as in claim 1, further comprising an extraction electrode coupled to the switching layer and biased to enable excess carriers to be rapidly removed from the switching layer.

3. An optical switch as in claim 1, further comprising an extraction electrode coupled to the switching layer and biased to enable carriers to be injected into the switching layer.

4. An optical switch as in claim 1, further comprising an input optical waveguide coupled to the thyristor and configured to carry the light beam to be directed through at least one of the plurality of semiconductor layers of the thyristor.

5. An optical switch as in claim 1, further comprising a first output optical waveguide coupled to the thyristor and configured to carry the light beam at one of the predetermined angle and the deflection angle.

6. An optical switch as in claim 5, further comprising a second output optical waveguide coupled to the thyristor and configured to carry the light beam at one of the predetermined angle and the deflection angle.

7. An optical switch as in claim 1, wherein the outer doped layer and the switching layer are comprised of a material having a negative conductivity type.

8. An optical switch as in claim 1, wherein the carriers are electrons.

9. An optical switch as in claim 1, wherein the outer doped layer and the switching layer are comprised of a material having a positive conductivity type.

10. An optical switch as in claim 1, wherein the carriers are holes.

11. An optical switch as in claim 1, wherein the outer doped layer and the switching layer are separated by a layer of a different conductivity type.

12. An optical switch as in claim 1, further comprising a waveguide coupled to at least one layer of the plurality of semiconducting layers, wherein the waveguide is configured to have a substantially similar index of refraction as the at least one layer.

13. An optical switch as in claim 1, wherein the thyristor is configured to be biased at a selected rate to modulate the light beam that exits the thyristor at one of the deflection angle and the predetermined angle.

14. An optical switch as in claim 1, wherein the thyristor is configured to be biased at a selected rate to switch the light beam that exits the thyristor at one of the deflection angle and the predetermined angle.

15. A method of making a fast injection optical switch for redirecting an optical beam, comprising:

forming a thyristor having a plurality of semiconducting layers including alternating positive and negative conductivity types, wherein the plurality of semiconducting layers includes an outer doped layer and a switching layer;

configuring an area of the thyristor to receive a light beam to be directed through at least one of the plurality of semiconducting layers and exit the thyristor at a predetermined angle; and

connecting at least two electrodes to the thyristor to enable a voltage to be applied to enable carriers from the outer doped layer to be directed to the switching layer, wherein sufficient carriers are directed to the switching layer to provide a change in refractive index of the switching layer to redirect at least a portion of the light beam to exit the thyristor at a deflection angle different than the predetermined angle.

16. A method as in claim 15, further comprising coupling an extraction electrode to the switching layer to enable excess carriers to be rapidly removed from the switching layer.

17. A method as in claim 15, further comprising coupling the thyristor to an input optical waveguide to transmit the light beam through the at least one of the plurality of semiconducting layers.

18. A method as in claim 15, further comprising coupling the thyristor to a first output optical waveguide and a second output optical waveguide to receive the light beam from the thyristor at one of the deflection angle and the predetermined angle.