Parallel and WDM silicon photonics integration in information and communications technology systems

• US 9,261,754 B2
• Filed: 12/13/2013
• Issued: 02/16/2016
• Est. Priority Date: 12/13/2013
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Xu, Qing, Brunner, Robert, Lessard, Stephane
• Primary Examiner(s): Stahl, Mike
• Application Number:
  US14/106,359
• Publication Number:
  US 20150168803A1
• Time in Patent Office: 795 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G02B 6/12007 forming wavelength selective elements, e.g. multiplexer, demultiplexer
• CPC Class Codes: G02F 1/353 Frequency conversion, i.e. wherein a light beam is generated with frequency components different from those of the incident light beams
• CPC Class Codes: G02F 1/365 in an optical waveguide structure G02F1/377, G02F1/395 take precedence
• CPC Class Codes: G02F 2/004 Transferring the modulation of modulated light, i.e. transferring the information from one optical carrier of a first wavelength to a second optical carrier of a second wavelength, e.g. all-optical wavelength converter
• CPC Class Codes: G02F 2/006 All-optical wavelength conversion
• CPC Class Codes: H04J 14/0212 using optical switches or wavelength selective switches [WSS]
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0011 using wavelength conversion
• CPC Class Codes: H04Q 2011/0035 using miscellaneous components, e.g. circulator, polarisation, acousto/thermo optical

Abstract

A wavelength converter includes first silicon waveguides and second silicon waveguides intersecting the first silicon waveguides to form an arrayed waveguide. The arrayed waveguide receives optical data signals at the same wavelength at a first input and optical pump signals at different wavelengths at a second input. Microring resonators evanescently couple different ones of the first silicon waveguides to different ones of the second silicon waveguides. Each microring resonator is tuned to the wavelength of the optical data signals or one of the wavelengths of the optical pump signals, so that different combinations of the optical data signals and the optical pump signals are provided at an output of the arrayed waveguide. A non-linear optical media converts the wavelength of each combined optical signal at the output of the arrayed waveguide to yield wavelength converted signals each having a new dedicated wavelength.

Claims

1. A wavelength converter, comprising:

first silicon waveguides;

second silicon waveguides intersecting the first silicon waveguides to form an arrayed waveguide, the arrayed waveguide configured to receive optical data signals at the same wavelength at a first input and optical pump signals at different wavelengths at a second input;

microring resonators evanescently coupling different ones of the first silicon waveguides to different ones of the second silicon waveguides, each microring resonator tuned to the wavelength of the optical data signals or one of the wavelengths of the optical pump signals, so that different combinations of the optical data signals and the optical pump signals are provided at an output of the arrayed waveguide, wherein each combined optical signal has a composite wavelength comprising the wavelength of the optical data signal and one of the wavelengths of the optical pump signals; and

a non-linear optical media configured to convert the composite wavelength of each combined optical signal at the output of the arrayed waveguide to yield wavelength converted signals each having a new dedicated wavelength.

2. The wavelength converter of claim 1, wherein each of the first silicon waveguides has a first end for receiving one of the optical data signals and a second end for receiving the optical pump signals at one of the different wavelengths, and wherein the different combinations of the optical data signals and optical pump signals egress a first end of the second silicon waveguides.

3. The wavelength converter of claim 2, wherein each of the second silicon waveguides has a second end opposite the first end for receiving additional optical pump signals of a fixed wavelength that is offset from the wavelength of the optical data signals, and wherein the microring resonators tuned to the wavelength of the optical data signals are also tuned to the fixed wavelength of the additional optical pump signals so that different combinations of the optical data signals, the optical pump signals and the additional optical pump signals are present at the output of the arrayed waveguide.

4. The wavelength converter of claim 1, wherein each of the first silicon waveguides has a first end for receiving one of the optical data signals, wherein each of the second silicon waveguides has a first end for receiving the optical pump signals at one of the different wavelengths, and wherein the different combinations of the optical data signals and optical pump signals egress a second end of the second silicon waveguides opposite the first end.

5. The wavelength converter of claim 1, wherein the microring resonators tuned to the wavelength of the optical data signals are arranged in different groups of cascaded microring resonators, wherein adjacent ones of the cascaded microring resonators of the same group are evanescently coupled to one another, and wherein each group of cascaded microring resonators evanescently couples one of the first silicon waveguides to one of the second silicon waveguides through the cascaded microring resonators included in that group.

6. The wavelength converter of claim 1, further comprising:

third silicon waveguides for receiving the wavelength converted signals from the non-linear optical media; and

additional microring resonators evanescently coupled to the third silicon waveguides and configured to filter the wavelength converted signals based on the new dedicated wavelength of each wavelength converted signal.

7. The wavelength converter of claim 1, wherein the optical pump signals are input to the second silicon waveguides via a single mode fiber coupled to a laser source operable to generate the optical pump signals.

8. The wavelength converter of claim 1, wherein at least some of the microring resonators include heaters operable to change at least one of the coupling ratio, free spectral range and resonance frequency of the corresponding microring resonator by heating that microring resonator.

9. The wavelength converter of claim 1, wherein at least some of the microring resonators include a PN or PIN junction operable to change at least one of the coupling ratio, free spectral range and resonance frequency of the corresponding microring resonator.

10. The wavelength converter of claim 1, wherein the wavelength converted signals are combined into a single fiber or coupled directly to an AWGR (array waveguide grating router).

11. The wavelength converter of claim 1, wherein the microring resonators tuned to the wavelength of the optical data signals have individually-controllable bandwidths.

12. The wavelength converter of claim 1, wherein a first group of the microring resonators evanescently couple a first one of the first silicon waveguides to a first one of the second silicon waveguides in a first region of the arrayed waveguide at a first bandwidth, and a second group of the microring resonators evanescently couple a second one of the first silicon waveguides to a second one of the second silicon waveguides in a second region of the arrayed waveguide at a second bandwidth different than the first bandwidth.

13. The wavelength converter of claim 12, wherein the first group of microring resonators has a different number of microring resonators than the second group of microring resonators so that the first bandwidth is different than the second bandwidth.

14. The wavelength converter of claim 12, wherein the first group of microring resonators has different sized microring resonators than the second group of microring resonators so that the first bandwidth is different than the second bandwidth.

15. A method of wavelength conversion, the method comprising:

receiving optical data signals at the same wavelength at a first input of an arrayed waveguide and optical pump signals at different wavelengths at a second input of the arrayed waveguide, the arrayed waveguide comprising first silicon waveguides and second silicon waveguides intersecting the first silicon waveguides;

evanescently coupling different ones of the first silicon waveguides to different ones of the second silicon waveguides via microring resonators, each microring resonator tuned to the wavelength of the optical data signals or one of the wavelengths of the optical pump signals, so that different combinations of the optical data signals and the optical pump signals are provided at an output of the arrayed waveguide, wherein each combined optical signal has a composite wavelength comprising the wavelength of the optical data signal and one of the wavelengths of the optical pump signals; and

converting the composite wavelength of each combined optical signal at the output of the arrayed waveguide to yield wavelength converted signals each having a new dedicated wavelength.

16. The method of claim 15, wherein receiving the optical data signals at the first input of the arrayed waveguide and the optical pump signals at the second input of the arrayed waveguide comprises:

coupling the optical data signals to a first end of the first silicon waveguides; and

coupling the optical pump signals to a second end of the first silicon waveguides opposite the first end, so that the different combinations of the optical data signals and optical pump signals egress a first end of the second silicon waveguides.

17. The method of claim 16, further comprising:

receiving additional optical pump signals of a fixed wavelength that is offset from the wavelength of the optical data signals at a second end of the second silicon waveguides opposite the first end, and

wherein the microring resonators tuned to the wavelength of the optical data signals are also tuned to the fixed wavelength of the additional optical pump signals so that different combinations of the optical data signals, the optical pump signals and the additional optical pump signals are present at the output of the arrayed waveguide.

18. The method of claim 15, wherein receiving the optical data signals at the first input of the arrayed waveguide and the optical pump signals at the second input of the arrayed waveguide comprises:

coupling the optical data signals to a first end of the first silicon waveguides; and

coupling the optical pump signals to a first end of the second silicon waveguides, so that the different combinations of the optical data signals and optical pump signals egress a second end of the second silicon waveguides opposite the first end.

19. The method of claim 15, further comprising:

coupling the wavelength converted signals to third silicon waveguides; and

filtering the wavelength converted signals based on the new dedicated wavelength of each wavelength converted signal via additional microring resonators evanescently coupled to the third silicon waveguides.

20. The method of claim 15, further comprising:

coupling the optical pump signals to the second silicon waveguides via a single mode fiber coupled to a laser source operable to generate the optical pump signals.

21. The method of claim 15, further comprising:

heating at least some of the microring resonators to change at least one of the coupling ratio, free spectral range and resonance frequency of those microring resonators.

22. The method of claim 15, further comprising:

individually controlling the bandwidth of the microring resonators tuned to the wavelength of the optical data signals.

23. A method of manufacturing a wavelength converter, the method comprising:

forming first silicon waveguides and second silicon waveguides intersecting the first silicon waveguides to form an arrayed waveguide;

forming microring resonators at regions of the arrayed waveguide where the first and second silicon waveguides intersect, so that the microring resonators evanescently couple different ones of the first silicon waveguides to different ones of the second silicon waveguides, each microring resonator designed to be tuned to a wavelength of optical data signals or a wavelength of optical pump signals input to one or both of the silicon waveguides;

coupling a non-linear optical media to an output of the arrayed waveguide;

testing the arrayed waveguide to determine whether any of the microring resonators is mistuned to the wavelength for which it was designed; and

storing results of the testing in memory, the stored results indicating which of the microring resonators is mistuned.