Nonlinear optical processing for terabit communications


Our research explores optical processing methods to enable high bitrate optical fiber communications through terabaud super-channels and coherent modulations formats.

Optical processing is performed using processes such as four-wave mixing (FWM) and cross-phase modulation (XPM). To maximize system integration we use on-chip highly-non-linear waveguides, made in media such as chalcogenide glass or slow-light in silicon photonic crystals. We also leverage the power of reconfigurable optical processors based on liquid crystal on semiconductor (LCOS) technology.

Chalcogenide waveguide on-chip diagram

Figure 1: Highly non-linear chalcogenide (As2S3) glass waveguide on-chip.

Group Members

Mark Pelusi, Benjamin Eggleton


Steve Madden and Barry Luther-Davies (Australian National University)
Leif Oxenlowe (Technical University of Denmark, DTU)
Shu Namiki (AIST, Japan)
Thomas F. Krauss (University of York)

Low latency, ultra high bandwidth signal processing

We aim at replacing operations usually performed by Digital Signal Processing (DSP) with all-optical devices with a view to reduce latency and power consumption in optical data transmission. Both linear and non-linear pulse shaping devices are studied.

Operations demonstrated include:
· linear impairments (dispersion, higher orders of dispersion, differential group delay) monitoring and real-time cancellation of their fluctuations;
· demultiplexing of high baudrate optical time division multiplexed signals;
· all-optical matrix product between wavelength division multiplexed signals;
· compensation of linear crosstalk based on the above mentioned dot-product implementation;
· generation and comparison of hash codes for data integrity check upon propagation through a transmission link.

Linear optical processor diagram

Figure 2: Linear optical processor based on a wavelength-selective switch.

diagram and graph of Tbaud receiver

Figure 3: an on-chip terabaud time-domain demultiplexer based on FWM.

diagram of dispersion conpensation

Figure 4: automatic dispersion compensation of a TBaud signal using on-chip optical RF analyser.

Signal distortion compensation by ultra-fast nonlinear optical devices

We harness the ultra-fast Kerr nonlinear response in specially tailored nonlinear optical waveguides to undo the deleterious impairments suffered by high bit rate optical signals in long distance transmission in optical fibre stemming from the intensity dependant change in the fibre refractive index known as the Kerr effect. Our focus is to negate the nonlinear phase distortion associated with the Kerr effect in the transmission link by the means of all-optical signal processing via nonlinear optics to conjugate the phase of the signal field during propagating through the optical waveguide. This approach is being explored to improve the transmission performance for higher bit rate signals produced by the emerging complex multi-level amplitude/phase modulation formats combined with coherent detection, and both wavelength division and polarization state multiplexing. The innovative harnessing of nonlinear optics to overcome the limits on the maximum signal transmission distance and bit rate capacity can have an important role in next generation optical fibre communication systems in enabling the challenging ever increasing bandwidth demand to be met.

diagram and results of optical phase conjunction

Figure 5: optical phase conjugation for mitigation of non-linear impairments through fiber optical link.

Mode-division multiplexing

Mode Division Multiplexing (MDM) differentiates between independent channels propagating in a fibre based on their spatial properties. Using computer controlled holograms implemented on spatial light modulators (SLM), channels are converted to different spatial patterns as they are coupled into the fibre and a corresponding hologram is used at the receiver to recover the channels.

multiplexing and demultiplexing diagram

Figure 6: multiplexing and demultiplexing data channels onto the modes of a multimode fiber.

Phase-sensitive amplification on a chip

Phase sensitive amplification (PSA) occurs when all waves in a parametric mixing process such as four-wave mixing are present at the input. The gain then depends on the relative phase between the input waves. It is an extremely attractive function because it is capable of squeezing noise below the 3dB quantum limit experienced by EDFAs. It can also be used to build optical regenerators for phase-coded signals, increasing the performance of next-generation communications formats based on complex coherent modulation.
In this project, we have achieved an 11dB phase extinction ratio in an ultrashort silicon photonic crystal (PhC) waveguide by taking advantage of the slow-light enhanced nonlinearity and dispersion engineering capability of PhC waveguides. The key insight is that PSA is possible even in the presence of two-photon absorption and free carriers. The performance is sufficient to use on-chip PSA as a compact regenerator for data signals in an optical communications link.

diagram of phase-sensitive amplification

Figure 7: Phase-sensitive amplification in silicon photonic crystals: (a) FWM configuration, (b) experimental setup and (c) phase sensitive gain from experiments and simulations.

Selected Publications

  1. Mark Pelusi, Amol Choudhary, Takashi Inoue, David Marpaung, Benjamin J. Eggleton, Karen Solis-Trapala, Hung Nguyen Tan, and Shu Namiki,
    "Low noise frequency comb carriers for 64-QAM via a Brillouin comb amplifier,"
    Opt. Express 25, 17847-17863 (2017)
  2. Joel Carpenter, Benjamin Eggleton, Jochen Schröder,
    "Comparison of principal modes and spatial eigenmodes in multimode optical fibre,"
    Laser & Photonics Reviews, 1600259 (2016)
    DOI 10.1002/lpor.201600259
  3. Joel Carpenter, Benjamin J. Eggleton, and Jochen Schröder,
    "Complete spatiotemporal characterization and optical transfer matrix inversion of a 420 mode fiber,"
    Opt. Lett. 41, 5580-5583 (2016)
  4. Erik Agrell et al,
    Roadmap of optical communications,
    2016 J. Opt. 18 063002
  5. Elias Giacoumidis, Sofien Mhatli, Tu Nguyen, Son T. Le, Ivan Aldaya, Mary E. McCarthy, Andrew D. Ellis, and Benjamin J. Eggleton,
    "Comparison of DSP-based nonlinear equalizers for intra-channel nonlinearity compensation in coherent optical OFDM,"
    Opt. Lett. 41, 2509-2512 (2016)
  6. Blair Morrison, Yanbing Zhang, Mattia Pagani, Benjamin Eggleton, and David Marpaung,
    "Four-wave mixing and nonlinear losses in thick silicon waveguides",
    Opt. Lett. 41, 2418-2421 (2016),
    doi: 10.1364/OL.41.002418
  7. Chad Husko, Matthias Wulf, Simon Lefrancois, Sylvain Combrié, Gaëlle Lehoucq, Alfredo De Rossi, Benjamin J. Eggleton & L. Kuipers,
    "Free-carrier-induced soliton fission unveiled by in situ measurements in nanophotonic waveguides",
    Nature Communications 7: 11332 (2016)
  8. Yanbing Zhang, Chad Husko, Simon Lefrancois, Isabella H. Rey, Thomas F. Krauss, Jochen Schröder, and Benjamin J. Eggleton,
    "Cross-phase modulation-induced spectral broadening in silicon waveguides,"
    Opt. Express 24, 443-451 (2016)
    doi: 10.1364/OE.24.000443
  9. Elias Giacoumidis, Son T. Le, Mohammad Ghanbarisabagh, Mary McCarthy, Ivan Aldaya, Sofien Mhatli, Mutsam A. Jarajreh, Paul A. Haigh, Nick J. Doran, Andrew D. Ellis, and Benjamin J. Eggleton,
    "Fiber nonlinearity-induced penalty reduction in CO-OFDM by ANN-based nonlinear equalization,"
    Opt. Lett. 40, 5113-5116 (2015)
    doi: 10.1364/OL.40.005113
  10. H. Y. Jiang, L. S. Yan, Y. Pan, W. Pan, B. Luo, X. H. Zou, and B. J. Eggleton,
    "Microwave photonic comb filter with ultra-fast tunability,"
    Opt. Lett. 40, 4895-4898 (2015)
    doi: 10.1364/OL.40.004895
  11. Yanbing Zhang, Chad Husko, Simon Lefrancois, Isabella H. Rey, Thomas F. Krauss, Jochen Schröder, and Benjamin J. Eggleton,
    "Non-degenerate two-photon absorption in silicon waveguides: analytical and experimental study,"
    Opt. Express 23, 17101-17110 (2015)
  12. Andrea Blanco-Redondo, Daniel Eades, Juntao Li, Simon Lefrancois, Thomas F. Krauss, Benjamin J. Eggleton, and Chad Husko,
    "Controlling free-carrier temporal effects in silicon by dispersion engineering,"
    Optica 1, 299-306 (2014)
  13. Y. Zhang, C. Husko, J. Schröder, and B. J. Eggleton,
    "Pulse evolution and phase-sensitive amplification in silicon waveguides,"
    Opt. Lett. 39, 5329-5332 (2014)
  14. Yanbing Zhang, Jochen Schröder, Chad Husko, Simon Lefrancois, Duk-Yong Choi, Steve Madden, Barry Luther-Davies, and Benjamin J. Eggleton,
    "Pump-degenerate phase-sensitive amplification in chalcogenide waveguides,"
    J. Opt. Soc. Am. B 31, 780-787 (2014)
  15. Christelle Monat, Christian Grillet, Matthew Collins, Alex Clark, Jochen Schroeder, Chunle Xiong, Juntao Li, Liam O'Faolain, Thomas F. Krauss, Benjamin J. Eggleton, & David J. Moss,
    "Integrated optical auto-correlator based on third-harmonic generation in a silicon photonic crystal waveguide,"
    Nature Communications 5, Article number: 3246 doi:10.1038/ncomms4246
  16. Jochen Schröder, Liang Bangyuan Du, Joel Carpenter, Benjamin J. Eggleton, and Arthur J. Lowery
    "All-Optical OFDM With Cyclic Prefix Insertion Using Flexible
    Wavelength Selective Switch Optical Processing,"
    Lightwave Technology, Journal of , vol.32, no.4, pp.752,759, Feb.15, 2014 doi: 10.1109/JLT.2013.2288638,
  17. Yvan Paquot, Jochen Schröder, and Benjamin J. Eggleton,
    "Reconfigurable linear combination of phase-and-amplitude coded optical signals,"
    Opt. Express 22, 2609-2619 (2014)
  18. Joel Carpenter, Benjamin J. Eggleton, and Jochen Schröder,
    "Reconfigurable spatially-diverse optical vector network analyzer,"
    Opt. Express 22, 2706-2713 (2014)
  19. Joel Carpenter, Sergio G. Leon-Saval, Joel R. Salazar-Gil, Joss Bland-Hawthorn, Glenn Baxter, Luke Stewart, Steve Frisken, Michaël A. F. Roelens, Benjamin J. Eggleton, and Jochen Schröder, "1x11 few-mode fiber wavelength selective switch using photonic lanterns,"
    Opt. Express 22, 2216-2221 (2014)
  20. Joel Carpenter, Benjamin J. Eggleton, and Jochen Schröder,
    "110x110 optical mode transfer matrix inversion,"
    Opt. Express 22, 96-101 (2014)
  21. Trung D. Vo, Jiakun He, Eric Magi, Matthew J. Collins, Alex S. Clark, Brian G. Ferguson, Chunle Xiong, and Benjamin J. Eggleton,
    "Chalcogenide fiber-based distributed temperature sensor with sub-centimeter spatial resolution and enhanced accuracy,"
    Opt. Express 22, 1560-1568 (2014)
  22. Mark D. Pelusi,
    "Fiber looped phase conjugation of polarization multiplexed signals for pre-compensation of fiber nonlinearity effect,"
    Opt. Express 21, 21423-21432 (2013)
  23. M.D. Pelusi,
    “WDM Signal All-Optical Precompensation of Kerr Nonlinearity in Dispersion-Managed Fibers,”
    IEEE PHOTONICS TECHNOLOGY LETTERS Volume: 25 Issue: 1 Pages: 71-74 (2013)
  24. Joel Carpenter, Chunle Xiong, Matthew J. Collins, Juntao Li, Thomas F. Krauss, Benjamin J. Eggleton, Alex S. Clark, and Jochen Schröder,
    "Mode multiplexed single-photon and classical channels in a few-mode fiber,"
    Opt. Express 21, 28794-28800 (2013)
  25. Yvan Paquot, Jochen Schröder, Mark D. Pelusi, and Benjamin J. Eggleton,
    "All-optical hash code generation and verification for low latency communications,"
    Opt. Express 21, 23873-23884 (2013)
  26. Y. Zhang, C. Husko, J. Schroeder, S. Lefrancois, I. Rey, T. Krauss, and B. J. Eggleton, “Record 11 dB Phase Sensitive Amplification in Sub-millimeter Silicon Waveguides,” CLEO-PR post-deadline paper, PD1b-3 (2013)
  27. Richard Neo, Jochen Schröder, Yvan Paquot, Duk-Yong Choi, Steve Madden, Barry Luther-Davies, and Benjamin J. Eggleton, "Phase-sensitive amplification of light in a χ(3) photonic chip using a dispersion engineered chalcogenide ridge waveguide," Opt. Express 21, 7926-7933 (2013)
  28. Jochen Schröder, Michaël A. F. Roelens, Liang B. Du, Arthur J. Lowery, Steve Frisken, and Benjamin J. Eggleton, "An optical FPGA: Reconfigurable simultaneous multi-output spectral pulse-shaping for linear optical processing," Opt. Express 21, 690-697 (2013)
  29. B.J. Eggleton, T.D. Vo, R. Pant, J. Schroeder, M.D. Pelusi, D. Yong Choi, S.J. Madden, B. Luther-Davies, "Photonic chip based ultrafast optical processing based on high nonlinearity dispersion engineered chalcogenide waveguides," Laser & Photonics Reviews, Volume 6, Issue 1, pages 97–114, January 2012
    DOI: 10.1002/lpor.201100024
  30. Mark D. Pelusi and Benjamin J. Eggleton, "Optically tunable compensation of nonlinear signal distortion in optical fiber by end-span optical phase conjugation," Opt. Express 20, 8015-8023 (2012)
  31. Yvan Paquot, Jochen Schröder, Jürgen Van Erps, Trung D. Vo, Mark D. Pelusi, Steve Madden, Barry Luther-Davies, and Benjamin J. Eggleton, "Single parameter optimization for simultaneous automatic compensation of multiple orders of dispersion for a 1.28 Tbaud signal," Opt. Express 19, 25512-25520 (2011)
  32. T. D. Vo, H. Hu, M. Galili, E. Palushani, J. Xu, L. K. Oxenløwe, S. J. Madden, D.-Y. Choi, D. A. P. Bulla, M. D. Pelusi, J. Schröder, B. Luther-Davies, and B. J. Eggleton, "Photonic chip based transmitter optimization and receiver demultiplexing of a 1.28 Tbit/s OTDM signal," Opt. Express 18, 17252-17261 (2010)
  33. Mark Pelusi, Feng Luan, Trung D. Vo, Michael R. E. Lamont, Steven J. Madden, Douglas A. Bulla, Duk-Yong Choi, Barry Luther-Davies & Benjamin J. Eggleton "Photonic-chip-based radio-frequency spectrum analyser with terahertz bandwidth", Nature Photonics, doi:10.1038/nphoton.2009.001 (2009)