Apparatus for imparting phase shift to input waveform

Patent metadata

Field	Value
Publication number	US-9323284-B2
Application number	US-200913124305-A
Country	US
Kind code	B2
Filing date	Oct 14, 2009
Priority date	Oct 14, 2008
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

There is set forth in one embodiment an apparatus and method for imparting a phase shift to an input waveform for output of a converted waveform. In one embodiment, a phase shift can be provided by four wave mixing of an input waveform and a pump pulse. In one embodiment, there is set forth an apparatus and method for generating a high resolution time domain representation of an input waveform comprising: dispersing the input waveform to generate a dispersed input waveform; subjecting the dispersed input waveform to four wave mixing by combining the dispersed input waveform with a dispersed pump pulse to generate a converted waveform; and presenting the converted waveform to a detector unit. In one embodiment a detector unit can include a spectrometer (spectrum analyzer) for recording of the converted waveform and output of a record representing the input waveform.

First claim

We claim:

1. An apparatus comprising:
a first dispersive element through which an input waveform propagates;
an optical element for outputting an output waveform; and
a pump pulse input unit for input of a pump pulse into the optical element, the pump pulse input unit being coupled to the optical element, the pump pulse input unit having a second dispersive element through which the pump pulse propagates;
wherein the optical element and the pump pulse input unit define a temporal lens, wherein each of the first dispersive element and the pump pulse input unit are coupled to the optical element;
wherein the first dispersive element and the second dispersive element are configured so that a dispersion of the first dispersive element is matched with a dispersion of the second dispersive element;
wherein the apparatus is configured so that the input waveform and the pump pulse are combined by four wave mixing at the optical element, so that the output waveform is phase shifted relative to the input waveform.

2. The apparatus of claim 1 , wherein for coordinating a dispersion of the first dispersive element with the second dispersive element the second dispersive element and the first dispersive element have a 2:1 dispersion ratio.

3. The apparatus of claim 1 , wherein the optical element in which the input waveform and the pump pulse are combined by four wave mixing comprises a waveguide provided on a photonic chip.

4. The apparatus of claim 1 , wherein the first dispersive element and the pump pulse input unit are arranged so that the input waveform travels through one focal length of dispersion prior to reaching the optical element.

5. The apparatus of claim 1 , wherein the pump pulse input unit is provided by a pump pulse source and the second dispersive element.

6. The apparatus of claim 1 , wherein the apparatus further comprises a detector unit for detecting the output waveform.

7. The apparatus of claim 1 , wherein the apparatus further comprises a detector unit for detecting the output waveform, the detector unit having a spectrometer and a photodetector.

8. The apparatus of claim 1 , wherein the optical element is provided by a photonic waveguide and wherein the first dispersive element, the second dispersive element, and the photonic waveguide are incorporated into a photonic chip-scale device.

9. The apparatus of claim 8 , wherein the photonic waveguide is a semiconductor waveguide.

10. The apparatus of claim 1 , wherein the optical element is configured to include a dispersion that yields a conversion bandwidth of greater than 100 nm.

11. The apparatus of claim 1 , wherein the optical element is configured to include a dispersion that yields a conversion bandwidth of greater than 150 nm.

12. The apparatus of claim 1 , wherein the optical element is adapted to include a zero-group-velocity dispersion point in the C telecommunications band.

13. The apparatus of claim 1 , wherein the optical element is configured so that a signal peak power dynamic range of the optical element is 10 3 .

14. The apparatus of claim 1 , wherein the optical element is configured so that a signal peak power dynamic range of the optical element is within a range of 100 μW to 100 mW.

15. The apparatus of claim 1 , wherein the optical element is configured so that each of the input waveform the pump pulse and the output waveform are within the S, C, and L telecommunication bands.

16. The apparatus of claim 1 , wherein the apparatus is configured so that the peak optical power inside a waveguide included in the optical element is maintained at level sufficiently low for avoidance of self phase modulation.

17. The apparatus of claim 1 , wherein the apparatus is configured so that the peak optical power inside a waveguide included in the optical element is maintained sufficiently low for avoidance of two photon induced free carrier effects.

18. The apparatus of claim 1 , wherein the apparatus is configured so that the peak optical power inside a waveguide included in the optical element is maintained below 100 mW.

19. An apparatus for generating a representation of an input waveform, the apparatus comprising:
a first dispersive element through which the input waveform propagates,
an optical element for outputting an output waveform;
a pump pulse input unit for input of a pump pulse into the optical element, the pump pulse input unit being coupled to the optical element, the pump pulse input unit having a second dispersive element through which the pump pulse propagates; and
a detector unit for detecting the output waveform; wherein the optical element and the pump pulse input unit define a temporal lens,
wherein each of the first dispersive element and the pump pulse input unit are coupled to the optical element;
wherein the first dispersive element and the second dispersive element are configured so that a dispersion of the first dispersive element is matched with a dispersion of the second dispersive element; wherein the apparatus is configured so that the input waveform and the pump pulse are combined by four wave mixing at the optical element so that the output waveform is phase shifted relative to the input waveform.

20. The apparatus of claim 19 , wherein the detector unit includes each of a spectrometer and a photodetector.

21. The apparatus of claim 19 , wherein the apparatus includes a spectrometer substantially directly coupled to the optical element.

22. The apparatus of claim 19 , wherein the apparatus includes an output dispersive element having an output dispersion and wherein the first dispersive element has an input dispersion and wherein the apparatus is configured so that the condition

Res
M

M

≤

τ
pump

2

applies, where Res M is the resolution limit of the detector unit, τ pump is the pump pulsewidth and M is the magnification factor determined by the ratio of the output dispersion to the input dispersion.

23. The apparatus of claim 19 , wherein the apparatus includes an output dispersive element having an output dispersion and wherein the first dispersive element has an input dispersion and wherein the apparatus is configured so that the condition

Res
M

M

≈

τ
pump

2

applies, where ReS M is the resolution limit of the detector unit, τ pump is the pump pulsewidth and M is the magnification factor determined by the ratio of the output dispersion to the input dispersion.

24. An apparatus for generating a representation of an input waveform, the apparatus comprising:
a first dispersive element through which the input waveform propagates,
an optical element having a waveguide provided on a photonic chip, the waveguide having a zero-group-velocity disper

Assignees

• Foster Mark
• Gaeta Alexander
• Geraghty David
• Lipson Michal
• Salem Reza
• Foster Amy
• Univ Cornell

Inventors

• Foster Mark
• Gaeta Alexander
• Geraghty David
• Lipson Michal
• Salem Reza
• Foster Amy

Classifications

• G01J11/00

  Measuring the characteristics of individual optical pulses or of optical pulse trains · CPC title

• G01J2009/0226

  Fibres · CPC title

• G02B27/46

  Systems using spatial filters · CPC title

• G06E3/003 Primary

  forming integrals of products, e.g. Fourier integrals, Laplace integrals, correlation integrals; for analysis or synthesis of functions using orthogonal functions · CPC title

• G01J9/00

  Measuring optical phase difference (devices or arrangements for controlling the phase of light beams G02F1/01); Determining degree of coherence; Measuring optical wavelength (spectrometry G01J3/00) · CPC title