Transmission line driven slot waveguide mach-zehnder interferometers

• US 8,818,141 B1
• Filed: 06/27/2011
• Issued: 08/26/2014
• Est. Priority Date: 06/25/2010
• Status: Expired due to Fees

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Hochberg, Michael J., Baehr-Jones, Tom, Witzens, Jeremy
• Primary Examiner(s): Stahl, Mike
• Application Number:
  US13/169,882
• Time in Patent Office: 1,156 Days
• Field of Search: None
• US Class Current: 385/3
• CPC Class Codes: G02F 1/225 in an optical waveguide structure
• CPC Class Codes: H04B 10/505 using external modulation

Abstract

A Mach-Zehnder interferometer useful for analog or digital optical signal manipulation. In one example, the MZI is configured as an optical device that provides a balanced output. In another example, the MZI is configured as an optical device that provides a single ended output. Each device uses a silicon split or slotted wave guide having an electro-optically active material present within the slot. The balanced output device uses two slotted wave guides in push-pull configuration.

Claims

1. A Mach-Zehnder interferometer having a balanced output, comprising:

a slotted wave guide having at least two silicon elements defining a slot therebetween, said at least two silicon elements having an electro-optically active material disposed within said slot, and configured to apply an electromagnetic field to said electro-optically active material, said slotted waveguide configured as a first arm of said Mach-Zehnder interferometer, and an optical fiber configured as a second arm of said Mach-Zehnder interferometer;

an optical input port of said Mach-Zehnder interferometer configured to receive an optical signal comprising a signal component having a signal amplitude Psig and a power component having a power amplitude Pamp, said optical input port configured to apply said signal component to

said first arm of said Mach-Zehnder interferometer and configured to apply said power component to said second arm of said Mach-Zehnder interferometer;

an optical output port of said Mach-Zehnder interferometer configured to provide a balanced optical output signal; and

an electrical input port configured to receive an input electrical signal having a radio frequency component with instantaneous amplitude V, and having a driver configured to apply said radio frequency signal component as a data signal relative to a ground signal to said at least one of said silicon elements of said slotted wave guide.

2. The Mach-Zehnder interferometer of claim 1, wherein said Mach-Zehnder interferometer is configured to provide a balanced optical signal having an amplitude A1

3. The Mach-Zehnder interferometer of claim 1, wherein said input electrical signal is an analog signal.

4. The Mach-Zehnder interferometer of claim 1, wherein said input electrical signal is a digital signal.

5. The Mach-Zehnder interferometer of claim 1, wherein said Mach-Zehnder interferometer is configured to operate at a frequency of 10 GHz.

6. The Mach-Zehnder interferometer of claim 1, wherein said Mach-Zehnder interferometer is configured to operate at a frequency of 20 GHz.

7. The Mach-Zehnder interferometer of claim 1, wherein said Mach-Zehnder interferometer is configured to operate at a frequency of 50 GHz.

8. The Mach-Zehnder interferometer of claim 1, wherein said signal component having a signal amplitude Psig is unmodulated.

9. The Mach-Zehnder interferometer of claim 1, wherein said power component having a power amplitude Pamp is unmodulated.

10. The Mach-Zehnder interferometer of claim 1, further comprising a fiber optic link and a balanced photodetector receiver.

11. A Mach-Zehnder interferometer having a single-ended output, comprising:

a first slotted wave guide having at least two silicon elements defining a first slot therebetween, said at least two silicon elements having an electro-optically active material disposed within said first slot, a first of said at least two silicon elements configured as a ground conductor and a second of said at least two silicon elements configured as a signal conductor, said at least two silicon elements configured to apply an electromagnetic field to said electro-optically active material in a first direction, said first slotted waveguide configured as a first arm of said Mach-Zehnder interferometer, and

a second slotted wave guide having at least two silicon elements defining a second slot therebetween, said at least two silicon elements having an electro-optically active material disposed within said second slot, a first of said at least two silicon elements configured as a ground conductor and a second of said at least two silicon elements configured as a signal conductor, said at least two silicon elements configured to apply an electromagnetic field to said electro-optically active material in a second direction antiparallel to said first direction, said second slotted waveguide configured as a second arm of said Mach-Zehnder interferometer;

said silicon element of said first slotted wave guide configured as a signal conductor and said silicon element of said second slotted wave guide configured as a signal conductor being in electrical contact;

an optical input port of said Mach-Zehnder interferometer configured to receive an optical carrier signal, said optical input port configured to apply said optical carrier signal to said first arm of said Mach-Zehnder interferometer and to said second arm of said Mach-Zehnder interferometer;

an optical output port of said Mach-Zehnder interferometer configured to provide a single-ended optical output signal; and

an electrical input port configured to receive an input electrical signal having a radio frequency component with instantaneous amplitude V, and having a driver configured to apply said radio frequency signal component as a data signal relative to a ground signal to said silicon element of said first slotted wave guide configured as a signal conductor and to said silicon element of said second slotted wave guide configured as a signal conductor of, and to apply said ground signal to each of said first of said at least two silicon elements configured as a ground conductor of each of said first and second slotted wave guides;

said Mach-Zehnder interferometer configured to provide at said optical output port a single-ended optical signal proportional to 2 times V.

12. The Mach-Zehnder interferometer of claim 11, wherein said input electrical signal is an analog signal.

13. The Mach-Zehnder interferometer of claim 11, wherein said input electrical signal is a digital signal.

14. The Mach-Zehnder interferometer of claim 11, wherein said Mach-Zehnder interferometer is configured to operate at a frequency of 10 GHz.

15. The Mach-Zehnder interferometer of claim 11, wherein said Mach-Zehnder interferometer is configured to operate at a frequency of 20 GHz.

16. The Mach-Zehnder interferometer of claim 11, wherein said Mach-Zehnder interferometer is configured to operate at a frequency of 50 GHz.

17. The Mach-Zehnder interferometer of claim 11, further comprising a fiber optic link and a photodetector receiver.

18. The Mach-Zehnder interferometer of claim 17, wherein said photodetector receiver comprises a transimpedance amplifier.