Optical Turing Machine

The Optical Turing Machine (OTM) is an effort to develop optical Tbps in-network processing.

• It seeks to unify communication and computation using a single encoding format.
• It provides processing required for in-transit data, e.g., to support:
  • Network packet processing
  • Big data filtering
  • Bulk network security
• It aims to support serial, high-density encodings for efficient high-speed, long distance communication
• It leverages the native properties of optical mixing to support transformational, rather than switched processing.

Key observations:

• Data must be encoded digitally.
  • Analog encodings accumulate noise when composed (cascaded) or recirculated (as for memory).
• Data must be recirculated.
  • Without recirculation, only combinatorial logic can be supported.
  • Higher levels of computation, such as finite state machines, push-down automata, and Turing machines are required to compute more complex algorithms. These require (respectively) a single state, a set of states in which only one can be modified, and a set of states in which any can be modified – and state requires recirculation.
• Data must be encoded using M-PSK.
  • Binary encodings are too slow and amplitude-keyed encodings (PAM, QAM) require value-dependent processing.
• Data must be regenerated while retaining its semantics.
  • Differential regeneration is very effective but prevents composition and recirculation.
  • For M-PSK, this necessitates phase squeezing (phase-sensitive amplification, or PSA).
  • PSA must be supported natively, without needing a pilot, reference, or conjugate to experience the same noise, e.g., “degenerate PSA”.
• Computation requires a field (for algebra), switching (for reprogrammability), and phase squeezing (for carry generation).
  • Algebra requires a field, i.e., a ring with two operators that satisfy the properties of a group.
• Data processing requires optical mixing (three-wave or four-wave, i.e., TWM or FWM).
  • Mixing supports Tbps and beyond data rates, whereas switching is limited due to the transmission effects of the drivers needed to modulate fields to vary bulk properties.
• A demonstration of the above requires hybrid integrated circuit technology.
  • Macroscopic, bench-top devices introduce phase instabilities that cannot be compensated. Integrated approaches allow the use of phase-aligned sources (e.g., combs) and reduce sensitivity to environmental disturbances (thermal, mechanical).
• Current approaches fall into two categories:
  • “Field of Dreams” (from the movie of the same name) – exploring the design space by building new components. Many of these approaches directly interfere with computation, component composition, or communication using a single format.
  • “The Aluminum Feather” – develop solutions inspired from existing successes, such as electronic computation, by literal translation of concepts. We coined this term to refer to an analogous approach to airplane design: birds fly, birds are made of living matter, birds use feathers — so if we want to build an aluminum bird (an airplane), we clearly need aluminum feathers. This points out the hazard of applying a conceptual homomorphism without context – i.e., translating ideas literally (transliteration) vs. translating the concepts.
  • OTM uses simultaneous consideration of the requirements for computation and communication to avoid these hazards.

Overview:

• SUMMARY: Click here for a one-page summary.
• SLIDES: J. Touch, “An Optical Turing Machine for Native Computing of Modulated Nework Data,” IEEE Computer Communications Workshop (CCW), Sedona, AZ, Nov. 2012.
• FIRST PAPER: J. Touch, A. Willner, “Native Digital Processing for Optical Networking,” Proc. IEEE Third Int’l. Conference on Future Generation Communication Technologies (FGCT), Aug. 2014.
• SUMMARY PAPER: J. Touch, Y. Cao, M. Ziyadi, A. Almaiman, A. Mohajerin-Ariaei, A.E. Willner, “Digital optical processing of optical communications: Towards an Optical Turing Machine,” Nanophotonics, Special Issue on Optical Computing, V6, N3, May, 2017, pp. 507-530.

Complete list of related publications:

OTM architecture and system

• J. Touch, Y. Cao, M. Ziyadi, A. Almaiman, A. Mohajerin-Ariaei, A.E. Willner, “Digital optical processing of optical communications: Towards an Optical Turing Machine,” Nanophotonics, Special Issue on Optical Computing, V6, N3, May, 2017, pp. 507-530.
• J. Touch, Y. Cao, M. Ziyadi, A. Almainman, A. Mohajerin Araiei, A. E. Willner, “A Candidate Approach for Optical In-Network Computation,” invited paper, IEEE Summer Topicals, July 2016.
• J. Touch, A. Willner, “Native Digital Processing for Optical Networking,” Proc. IEEE Third Int’l. Conference on Future Generation Communication Technologies (FGCT), Aug. 2014.

Regeneration

• Differential (delay-based):
  • A. Mohajerin-Ariaei, M. Ziyadi, Y. Cao, A. Almaiman, F. Alishahi, A. Fallahpour, C. Bao, P. Liao, B. Shamee, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Demonstration of Tunable Mitigation of Interchannel Interference of Spectrally Overlapped 16-QAM/QPSK Data Channels using Wave Mixing of Delayed Copies,” OFC 2017.
  • Y. Cao, M. Ziyadi, A. Mohajerin-Ariaei, A. Almaiman, P. Liao, C. Bao, F. Alishahi, A. Fallahpour, B. Shamee, J-Y. Yang, Y. Akasaka, M. Sekiya, M. Tur, C. Langrock, M. Fejer, J. Touch, A. Willner, “Reconfigurable Optical Inter-Channel Interference Mitigation for Spectrally Overlapped QPSK Signals using Nonlinear Wave Mixing in Cascaded PPLN Waveguides,” Optics Letters, V41 N14, July 2016, pp. 3233-3236.
  • A. Mohajerin-Ariaei, M. Ziyadi, M. Chitgarha, A. Almaiman, Y. Cao, J.-Y. Yang, Y. Akasaka, M. Sekiya, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Phase noise mitigation of QPSK signal utilizing phase-locked multiplexing of signal harmonics and amplitude saturation,” Optics Letters, V40 N14, 2015.
  • A. Mohajerin-Ariaei, Y. Akasaka, J.-Y. Yang, M. R. Chitgarha, M. Ziyadi, Y. Cao, A. Almaiman, J. Touch, M. Tur, M. Sekiya, S. Takasaka, R. Sugizaki, C. Langrock, M. M. Fejer, A. E. Willner, “Bit-Rate-Tunable Noise Mitigation of 30-Gbaud QPSK Data Using Differential Phase Quantization and Amplitude Saturation,” ECOC,  2014.
  • A. Mohajerin-Ariaei, M. Chitgarha, M. Ziyadi, S. Khaleghi, A. Almaiman, M. Willner, J. Touch, J.-Y. Yang, Y. Akasaka, M. Sekiya, M. Tur, L. Paraschis, C. Langrock, M. Fejer, A. Willner, “Experimental Demonstration of All Optical Phase Noise Mitigation of 40-Gbits/s QPSK Signals by Mixing Differentially Delayed Nonlinear Products,” OFC 2014.
  • M. Chitgarha, S. Khaleghi, M. Ziyadi, W. Daab, A. Mohajerin-Ariaei, D. Rogawski, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Demonstration of all-optical phase noise suppression scheme using optical nonlinearity and conversion/dispersion delay,” Optics Letters, V39 N10, 2014.
  • M. Chitgarha, S. Khaleghi, M. Ziyadi, W. Daab, A. Mohajerin-Ariaei, D. Rogawski, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “All-Optical Phase Noise Suppression Using Optical Nonlinear Mixing Combined with Tunable Optical Delays,” OFC 2013.
• Non-degenerate PSA:
  • J.-Y. Yang, Y. Akasaka, M. Ziyadi, A. Mohajerin-Ariaei, Y. Cao, A. Almaiman, I. Kim, J. Touch, A. Willner, M. Sekiya, “PSA and PSA-Based Optical Regeneration for Extending the Reach of Spectrally Efficient Advanced Modulation Formats,” invited paper, IEEE Summer Topicals 2015.
  • M. Ziyadi, A. Mohajerin-Ariaei, J.-Y. Yang, Y. Akasaka, M. Chitgarha, S. Khaleghi, A. Almaiman, A. Abouzaid, J. Touch, M. Sekiya, “Experimental Demonstration of Optical Regeneration of DP-BPSK/QPSK Using Polarization-Diversity PSA,” CLEO 2014.
  • J-Y. Yang, M. Ziyadi, Y. Aksaka, S. Khaleghi, M. Chitagarha, J. Touch, M. Sekiya, “Investigation of Polarization-Insensitive Phase Regeneration Using Polarization-Diversity Phase-Sensitive Amplifier,” ECOC 2013.
• Other variants of PSA:
  • Y. Cao, A. Almaiman, Y. Akasaka, F. Alishahi, M. Ziyadi, A. Mohajerin-Ariaei, C. Bao, P. Liao, A. Fallahpour, B. Shamee, T. Ikeuchi, S. Takasaka, R. Sugizaki, J. Touch, M. Tur, A. E. Willner, “Experimental Demonstration of Raman-Assisted Phase Sensitive Amplifier with Reduced ASE Noise Level and More than 25dB Net Gain,” OFC 2017.
  • A. Almaiman, Y. Cao, M. Ziyadi, A. Mohajerin-Ariaei, P. Liao, C. Bau, F. Alishahi, B. Shamee, N. Ahmed, A.J. Willner, Y. Akasaka, T. Ikeuchi, S. Takasaka, R. Sugizaki, S. Wilkinson, J. Touch, M. Tur, A.E. Willner, “Experimental Demonstration of Phase-Sensitive Regeneration of a BPSK Channel without Phase-Locked Loop using Brillouin Amplification,” Optics Letters, V41 N23, Dec. 2016, pp. 5434-5437.
  • A. Almaiman, Y. Cao, M. Ziyadi, A. Mohajerin-Araei, P. Liao, C. Bao, F. Alishahi, A. Fallahpour, B. Shamee, J. Touch, Y. Akasaka, T. Ikeuchi, S. Wilkinson, M. Tur, A. Willner, “Experimental Demonstration of Phase-Sensitive Regeneration of a 20-40 Gb/s QPSK Channel without Phase-Locked Loop using Brillouin Amplification,” ECOC 2016.
  • Y. Cao, F. Alishahi, Y. Akasaka, M. Ziyadi, A. Almaiman, A. Mohajerin-Araei, C. Bao, P. Liao, A. Fallahpour, B. Shamee, T. Ikeuchi, S, Takasaka, R. Sugizaki, J. Touch, M. Tur, A. Willner, “Experimental Investigation of Quasi-Periodic Power Spectrum in Raman-Assisted Phase Sensitive Amplifier for 10/20/50-Gbaud QPSK and 10-Gbaud 16QAM Signals,” ECOC 2016.
  • A. Almaiman, Y. Cao, M. Ziyadi, P. Liao, A. Mohajerin Ariaei, C. Bao, F. Alishah, A. Fallahpour, B. Shamee, A. Willner, N. Ahmed, A. Youichi, T. Ikeuchi, S. Wilkinson, M. Tur, and A. Willner, “Experimental Demonstration of Phase-Sensitive Regeneration of a 10-20 Gb/s BPSK Channel without a Phase-Locked Loop using Brillouin Amplification,” OFC 2016.

Regeneration-related issues:

• J. Touch, M. Ziyadi, A. Abouzaid, M. Chitgarha, S. Khaleghi, A. Mohajerin-Ariaei, Y. Akasaka, J.-Y. Yang, M. Sekiya, “Passive Digital Algorithmic Stabilization of Optical Phase,” CLEO 2014.
• J. Touch, A. Mohajerin-Ariaei, M. Chitgarha, M. Ziyadi, S. Khaleghi, Y. Akasaka, J.-Y. Yang, M. Sekiya, “The Impact of Errors on Differential Optical Processing,” USC/ISI Tech. Report ISI-TR-690, Mar. 2014.

Amplitude squeezing (multilevel):

• Y. Cao, M. Ziyadi, Y. Akasaka, A. Mohajerin-Ariaei , J.-Y. Yang, A. Almaiman, P. Liao, S. Takasaka. R. Sugizaki, J. Touch. M. Sekiya, M. Tur, A. Willner, “All optical signal level swapping and multilevel amplitude noise mitigation based on different regions of optical parametric gain,” Optics Letters, V41 N4, 2016.
• Y. Cao, M. Ziyadi, Y. Akasaka, A. Mohajerin-Ariaei, J.-Y. Yang, A. Almaiman, P. Liao, S. Takasaka, R. Sugizaki, J. Touch, . Sekiya, M. Tur, A. Willner, “Experimental Demonstration of Optical Signal Level Swapping and Multi-level Amplitude Noise Mitigation using Three Parametric Gain Regions,” OFC 2015.

Signal generation (high-speed):

• Y. Cao, A. Almaiman, M. Ziyadi, A. Mohajerin-Ariaei, C. Bao, P. Liao, F. Alishahi, A. Fallahpour, Y. Akasaka, T. Ikeuchi, C. Langrock, M. Fejer, J. Touch, M. Tur, A. E. Willner, “Experimental Demonstration of Tunable Optical Channel Slicing and Stitching to Enable Dynamic Bandwidth Allocation,” OFC 2017.
• A. Mohajerin Ariaei, M. Ziyadi, A. Almaiman, Y. Cao, C. Bao, P. Liao, B. Shamee, F. Alishahi, A. Fallahpour, M. R. Chitgarha, A. Willner, Y. Akasaka, T. Ikeuchi, S. Wilkinson, J. Touch, M. Tur, C. Langrock, M. Fejer, and A. Willner, “Demonstration of Multiplexing and Transmission of QPSK-to-16QAM Channels over 100 km using Wave Mixing for Aggregation and Noise Mitigation,” CLEO 2016.
• M. Ziyadi, M. Chitgarha, A. Mohajerin-Ariaei, S. Khaleghi, A. Almaiman, M. Willner, J. Touch, Y. Akasaka, J.-Y. Yang, M. Sekiya, M. Tur, L. Paraschis, C. Langrock, M. Fejer, A. Willner “Experimental Demonstration of Optical Nyquist Generation of 32-Gbaud QPSK using a Comb-based Tunable Optical Tapped-Delay-Line FIR Filter,” OFC 2014.
• M. R. Chitgarha, S. Khaleghi, M. Ziyadi, A. Almaiman, A. Mohajerin-Ariaei, O. Gerstel, L. Paraschis, C. Langrock, M. Fejer, J. Touch, A. Willner, “Demonstration of tunable optical generation of higher-order modulation formats using nonlinearities and coherent frequency comb,” Optics Letters, V39 N16, 2014.
• M. Chitgarha, M. Ziyadi, S. Khaleghi, A. Almaiman, A. Mohajerin-Ariaei, L. Paraschis, O. Gerstel, C. Langrock, M. Fejer, J. Touch, A. Willner, “Demonstration of Tunable Optical Generation of Higher-Order Modulation Formats using Nonlinearities and Coherent Frequency Comb,” CLEO 2013.

Signal reception (high-speed):

• Y. Cao, M. Ziyadi, A. Almaiman, A. Mohajerin-Ariaei, P. Liao, C. Bao, F. Alishahi, A. Fallahpour, B. Shamee, A. J. Willner, Y. Akasaka, T. Ikeuchi, S. Wilkinson, C. Langrock, M. Fejer, J. Touch, M. Tur, A. E. Willner, “Pilot-tone based self-homodyne detection using optical nonlinear wave mixing,” Optics Letters, V42 N9, May 2017, pp. 1840-1843.
• A. Fallahpour, M. Ziyadi, A. Mohajerin-Ariaei, Y. Cao, A. Almaiman, F. Alishahi, C. Bao, P. Liao, B. Shamee, L. Paraschis, M. Tur, C. Langrock, M. Fejer, J. Touch, A. Willner, “Experimental Demonstration of Tunable Optical De-aggregation of Each of Multiple Wavelength 16-QAM Channels into Two 4-PAM Channels,” OFC 2017.
• A. Mohajerin-Ariaei, M. Ziyadi, A. Almaiman, Y. Cao, F. Alishahi, M. R. Chitgarha, A. Fallahpour, C. Bao, P. Liao, B. Shamee, Y. Akasaka, J.-Y. Yang, M. Sekiya, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Simultaneous all-optical phase noise mitigation and automatically locked homodyne reception of an incoming QPSK data signal,” Optics Letters, V41 N20, Oct. 2016, pp. 4779-4782.
• M. Ziyadi, A. Ariaei, Y. Cao, A. Almaiman, A. Fallahpour, C. Bao, F. Alishahi, P. Liao, B. Shamee, L. Paraschis, M. Tur, C. Langrock, M. Fejer, J. Touch, Y. Akasaka, T. Ikeuchi, A. Willner, “Tunable Optical De-aggregation of a 40-Gbit/s 16-QAM Signal into Two 20-Gbit/s 4-PAM Signals using a Coherent Frequency Comb and Nonlinear Processing,” CLEO 2016.
• F. Alishahi, Y. Cao, A. Mohajerin-Ariaei, A. Fallahpour, A. Almainman, C. Bao, P. Liao, A. J. Willner, B. Shamee, Y. Akasaka. T. Ikeuchi, S. Takasakla, R. Sugizaki, J. Touch, M. Tur, A. E. Willner “Tunable All-Optical WDM Channel Selection using Raman Assisted Cascaded Parametric Amplification,” CLEO 2016.
• A. Almaiman, M. Ziyadi, A. Mohajerin-Ariaei, Y. Cao, M. Chitgarha, P. Liao, C. Bao, B. Shamee, N. Ahmed, F. Alishahi, A. Fallahpour, Y. Akasaka, J-Y. Yang, M. Sekiya, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Experimantal demonstration of tunable homodyne detection of WDM and dual-polarization PSK channels by automatically locking the channels to a local pump laser using nonlinear mixing,” Optics Letters,  V41 N12, 2016.
• M. Ziyadi, M. Chitgarha, A. Mohajerin-Ariaei, Y. Cao, S. Khaleghi, A. Almaiman, J. Touch, L. Paraschis, M. Tur, C. Langrock, M. Fejer, A. Willner, “Optical Channel Deaggregation of Quadrature-phase-shift-keying and Eight-phase-shift-keying Data Using Using Mapping onto Constellation Axes,” Optics Letters, V40 N21, 2015.
• A. Almaiman, M. Ziyadi, A. Mohajerin Ariaei, Y. Cao, M. R. Chitgarha, P. Liao, Y. Akasaka, J.-Y. Yang, J. Touch, M. Sekiya, C. Langrock, M. Fejer, M. Tur, A. Willner, “Experimental Demonstration of Tunable Homodyne Detection for Two Channels Simultaneously using Nonlinear Optical Signal Processing to Automatically Lock a Single “Local” Pump Laser to Two 20-Gbaud BPSK Data Signals,” CLEO 2015.
• M. Ziyadi, A. Mohajerin Ariaei, A. Almaiman, Y. Cao, M. Chitgarha, P. Liao, Y. Akasaka, J.-Y. Yang, M. Sekiya, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Experimental Demonstration of Tunable and Automatically-Locked Homodyne Detection for Dual-Polarization 20-32-Gbaud QPSK Channels using Nonlinear Mixing and Polarization Diversity,” CLEO 2015.
• M. Ziyadi, A. Mohajerin Ariaei, M. Chitgarha, Y. Cao, A. Almaiman, Y. Akasaka, J.-Y. Yang, G. Xie, P. Liao, M. Sekiya, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Demonstration of Tunable and Automatic Frequency/Phase Locking for Multiple-Wavelength QPSK and 16-QAM Homodyne Receivers using a Single Nonlinear Element,” CLEO 2015.
• A. Mohajerin Ariaei, M. Ziyadi, A. Almaiman, Y. Cao, M. Chitgarha, Y. Akasaka, J.-Y. Yang, M. Sekiya, J. Touch, M. Tur, C. Langrock, M. Fejer, A. Willner, “Experimental Demonstration of Simultaneous Phase Noise Suppression and Automatically Locked Tunable Homodyne Reception for a 20-Gbaud QPSK Signal,” CLEO 2015.
• A. Mohajerin Ariaei, M. Ziyadi, M.-R. Chitgarha, A. Almaiman, Y. Cao, Y. Akasaka, J.-Y. Yang, M. Sekiya, J. Touch, M. Tur, S. Takasaka, R. Sugizaki, C. Langrock, M. Fejer, A. Willner, “Experimental Demonstration of Tunable Phase-Noise Mitigation and Automatic Frequency/Phase Locking for a 20-32 Gbaud QPSK Homodyne Receiver using Optical Mixing of Nonlinearly Generated Higher Harmonics,” OFC 2015.
• M. Chitgarha, Y. Cao, A. Mohajerin-Ariaei, M. Ziyadi, S. Khaleghi, A. Almaiman, J. Touch, C. Langrock, M. Fejer, A. Willner, “Tunable Homodyne Detection of an Incoming QPSK Data Signal using Two Fixed Pump Lasers,” IEEE/OSA Journal of Lightwave Technology, (invited paper), Apr. 2015.
• M. Chitgarha, Y. Cao, A. Mohajerin-Ariaei, M. Ziyadi, S. Khaleghi, A. Almaiman, J. Touch, C. Langrock, M. Fejer, A. Willner, “Tunable Homodyne Detection using Nonlinear Optical Signal Processing to Automatically Lock a ‘Local’ Pump Laser to an Incoming 20-to-40-Gbaud QPSK Data Signal,” ECOC 2014.
• M. Ziyadi, M. Chitgarha, A. Mohajerin-Ariaei, Y. Cao, S. Khaleghi, A. Almaiman, J. Touch, L. Paraschis, M. Tur, C. Langrock, M. Fejer, A. Willner, “Optical Channel De-aggregator of 30-Gbaud QPSK and 20-Gbaud 8-PSK Data Using Mapping onto Constellation Axes,” ECOC 2014.

Uses of optical computation:

• J. Touch, A.-H. Badawy, V. Sorger, “Optical Computing,” Nanophotonics, Special Issue on Optical Computing, V6, N3, May, 2017, pp. 503-505.
• J. Touch, J. Bannister, S. Suryaputra, A. Willner, “A Design for an Internet Router with a Digital Optical Data Plane,” Applied Sciences, Spec. Issue on Optical Modulators and Switches, V7 N2, 143, Feb. 2017, pp. 1-19, doi:10.3390/app7020143.
• J. Touch, J. Bannister, S. Suryaputra, A. Willner, “A design for an Internet router with a digital optical data plane,” Invited paper, Photonics West, 2014.
• J. Touch, S. Suryaputra, J. Bannister, A. Willner, “Optical Packet Switch Using Forward-Shift SDLs,” OECC-PS, Jul. 2013.
• S. Suryaputra, J. Touch, J. Bannister, “The Case of a Precognition Optical Packet Switch,” Proc. IEEE High-Speed Networks Workshop, Apr. 2009.
• J. Touch, “Components developed for all-optical Internet router,” SPIE Newsroom article (PDF also available), Sept. 24, 2008.

Algorithms for optical computation:

• J. McGeehan, S. Kumar, D. Gurkan, S. Motaghian Nezam, J. Bannister, J. Touch, & A. Willner “All-Optical Decrementing of a Packet’s Time-To-Live (TTL) Field and Subsequent Dropping of a Zero-TTL Packet,” IEEE/OSA Journal of Lightwave Technology, Special Issue on Optical Networks, V21 N11, Dec. 2003, pp. 2746-2752.

Other related papers

• A. Mohajerin-Ariaei, M. Ziyadi, M. R. Chitgarha, and A. E. Willner, “All-optical Implementation of Signal Processing Functions,” Invited Paper, Society of Photo-Instrumentation Engineers (SPIE) Photonics West, Optical Metro Networks and Short-Haul Systems VII Conference, paper 9388-7, San Francisco, CA, Feb. 2015.
• R. Van Meter, S. Suzuki, S. Nagayama, T. Satoh, T. Matsuo, A. Taherkhani, S. Devitt, J. Touch, “Large-Scale Simulation of the Quantum Internet,” Proc., International Conference on Quantum Communication, Measurement and Computing (QCMC), Singapore, 2016.

OTM is supported in part by:

• NSF INSPIRE Grant #1344221
• NSF Center for Integrated Access Networks (CIAN) ERC
• USC/ISI New Research Initiative Grant