Reduced crosstalk photonic switch

Patent metadata

Field	Value
Publication number	US-10951964-B2
Application number	US-202016839597-A
Country	US
Kind code	B2
Filing date	Apr 3, 2020
Priority date	Mar 14, 2018
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

Described are various configurations of reduced crosstalk optical switches. Various embodiments can reduce or entirely eliminate crosstalk using a coupler that has a power-splitting ratio that compensates for amplitude imbalance caused by phase modulator attenuation. Some embodiments implement a plurality of phase modulators and couplers as part of a dilated switch network to increase overall bandwidth and further reduce potential for crosstalk.

First claim

What is claimed is:

1. A method for routing light using an optical switch, the method comprising:
receiving light at the optical switch, the optical switch having a physical shape that compensates for attenuation differences of internal light in the optical switch;
generating modulated light using an optical modulator in the optical switch, the modulated light exhibiting attenuation caused by the optical modulator; and
coupling the modulated light using the optical switch such that constructive interference occurs for a first output port of the optical switch and destructive interference occurs for a second output port of the optical switch due to the physical shape of the optical switch.

2. The method of claim 1 , wherein the optical switch comprises a coupler that exhibits the physical shape that compensates for the attenuation differences of the light in the coupler.

3. The method of claim 2 , wherein the coupler has tapered sides that modify a superposition of the light in the coupler.

4. The method of claim 3 , wherein the superposition of the light in the coupler is modified by the tapered sides such that a power splitting ratio of the coupler compensates for attenuation differences in the light in the coupler.

5. The method of claim 4 , wherein the power splitting ratio is t{circumflex over ( )}2/(1+t{circumflex over ( )}2), where t is a ratio of field transmission coefficients of the optical modulator.

6. The method of claim 4 , wherein the power splitting ratio is t/(1+t), where t is a ratio of field transmission coefficients of the optical modulator.

7. The method of claim 1 , wherein the optical modulator is a phase modulator that generates the modulated light using phase modulation.

8. The method of claim 7 , wherein generating the modulated light comprises shifting, using the phase modulator, a phase of a portion of the light in the optical switch by approximately 90 degrees.

9. The method of claim 7 , wherein generating the modulated light comprises shifting, using the phase modulator, a phase of a portion of the light in the optical switch by approximately 180 degrees.

10. The method of claim 1 , wherein the optical modulator generates the modulated light based on a quantity of embedded positive and negative carriers in the optical modulator.

11. The method of claim 1 , wherein the optical modulator is a first optical modulator and the optical switch comprises a second optical modulator, wherein the first optical modulator generates the modulated light while the second optical modulator is inactive.

12. The method of claim 11 , wherein the second optical modulator that is inactive passes light unmodulated.

13. An optical switch for routing light, the optical switch comprising:
an input port to receive the light;
a first output port;
a second output port; and
an optical modulator configured to generate modulated light, the modulated light exhibiting attenuation caused by the optical modulator, the optical switch having a physical shape that compensates for attenuation differences by causing constructive interference occurs for a first output port of the optical switch and destructive interference occurs for a second output port of the optical switch due to the physical shape of the optical switch.

14. The optical switch of claim 13 , wherein the optical switch comprises a coupler that exhibits the physical shape that compensates for the attenuation differences of the light in the coupler.

15. The optical switch of claim 14 , wherein the coupler has tapered sides that modify a superposition of the light in the coupler.

16. The optical switch of claim 15 , wherein the superposition of the light in the coupler is modified by the tapered sides such that a power splitting ratio of the coupler compensates for attenuation differences in the light in the coupler.

17. The optical switch of claim 13 , wherein the optical modulator is a phase modulator that generates the modulated light using phase modulation.

18. The optical switch of claim 13 , wherein the optical modulator generates the modulated light based on a quantity of embedded positive and negative carriers in the optical modulator.

19. The optical switch of claim 13 , wherein the optical modulator is a first optical modulator, and wherein the optical switch further comprises a second optical modulator, wherein the first optical modulator generates the modulated light while the second optical modulator is inactive.

20. The optical switch of claim 19 , wherein the second optical modulator that is inactive passes light unmodulated.

Assignees

• Juniper Networks Inc

Inventors

• Roth Jonathan Edgar

Classifications

• H04Q2011/0058

  Crossbar; Matrix · CPC title

• H04Q2011/0049

  Crosstalk reduction; Noise; Power budget · CPC title

• H04Q2011/0007

  Construction · CPC title

• H04Q11/0005 Primary

  Switch and router aspects · CPC title

• G02F1/212

  Mach-Zehnder type · CPC title