Integrated optics today is based upon chips of Si and InP. The future of this chip industry is probably contained in the thrust towards optoelectronic integrated circuits (OEICs) and photonic integrated circuits (PICs) manufactured in a high-volume foundry. We believe that reconfigurable OEICs and PICs, known as ROEICs and RPICs, constitute the ultimate embodiment of integrated photonics. This paper shows that any ROEIC-on-a-chip can be decomposed into photonic modules, some of them fixed and some of them changeable in function. Reconfiguration is provided by electrical control signals to the electro-optical building blocks. We illustrate these modules in detail and discuss 3D ROEIC chips for the highest-performance signal processing. We present examples of our module theory for RPIC optical lattice filters already constructed, and we propose new ROEICs for directed optical logic, large-scale matrix switching, and 2D beamsteering of a phased-array microwave antenna. In general, large-scale-integrated ROEICs will enable significant applications in computing, quantum computing, communications, learning, imaging, telepresence, sensing, RF/microwave photonics, information storage, cryptography, and data mining. 1. Introduction This paper focuses on reconfigurable chips and boards that can interface with free-space light beams and optical fibers. The stacked, layered 3D chip is an important new trend discussed here. One goal of this paper is to present a building-block theory of reconfigurables in which a system is formed by interconnecting fixed and changeable modules, each of which has a distinct function. Those functions are identified, and several examples of theory are given. Some examples pertain to chips already built; others are proposals for future chips. Over the next five years, the main optoelectronics research challenge is the large-scale integration (LSI) of low-energy reconfigurable photonics in a cost-effective manner. Our theory provides a framework for innovative R&D in LSI but does not answer basic questions about the function and architecture of new LSI chips. Readers of this paper are called upon to answer those questions. The semiconductor chip or substrate assumed in this paper is typically silicon or indium phosphide, but we will be agnostic about which materials system should be used. The wavelength of operation would be in the visible-through-mid-infrared [3], typically in the 1550 nm telecom/datacom wavelength band. Opto-electronics (OE) refers to a marriage of optics with electronics, whereas electro-optics (EO) signifies an
References
[1]
A. Hosseini, D. Kwong, Y. Zhang et al., “On the fabrication of three-dimensional silicon-on-insulator based optical phased array for agile and large angle laser beam steering systems,” Journal of Vacuum Science and Technology B, vol. 28, no. 6, pp. C6O1–C6O7, 2010.
[2]
M. Qi, “Design and fabrication of high-Q hollow cavities in few-layer 3D photonic crystals,” AFOSR semiconductor nano-membrane MURI review, Austin, Tex, September 2010.
[3]
R. Soref, “Toward silicon-based longwave integrated optoelectronics (LIO),” in Silicon Photonics III, vol. 6898 of Proceedings of SPIE, January 2008.
[4]
E. J. Norberg, R. S. Guzzon, J. S. Parker, and L. A. Coldren, “Programmable photonic filters from monolithically cascaded filter stages,” in Proceedings of the Optical Society of America, Conference on Integrated Photonics Research, Monterey, Calif, USA, July 2010, paper ITuC3.
[5]
S. Ibrahim, L. W. Luo, S. S. Djordjevic, et al., “Fully reconfigurable silicon photonic lattice filters with four cascaded unit cells,” in Proceedings of the Optical Fiber Communications Conference, OSA/OFC/NFOEC, San Diego, Calif, USA, March 2010, paper OWJ5.
[6]
R. S. Guzzon, E. J. Norber, J. S. Parker, and L. A. Coldren, “Highly programmable optical filters integrated on InP-InGaAsP with tunable inter-ring coupling,” in Proceedings of the Optical Society of America, Conference on Integrated Photonics Research, Monterey, Calif, USA, July 2010, paper ITuC4.
[7]
K. Bergman, http://lightwave.ee.columbia.edu/?s=research&p=large-scale_fabrics.
[8]
S. Namiki, “Optical routing networks,” in MIT Microphotonics Center Fall Meeting, Cambridge, Mass, USA, October 2010.
[9]
M. R. Watts, “Scaling data transport with integration,” in MIT Microphotonics Center Fall Meeting, Cambridge, Mass, USA, October 2010.
[10]
M. R. Watts, “Adiabatic microring resonators,” Optics Letters, vol. 35, no. 19, pp. 3231–3233, 2010.
[11]
S. Fathpour and N. A. Riza, “Silicon-photonics-based wideband radar beamforming: basic design,” Optical Engineering, vol. 49, no. 1, Article ID 018201, 2010.
[12]
R. A. Soref, S.-Y. Cho, W. Buchwald, R. E. Peale, and J. Cleary, “Silicon Plasmonic Waveguides,” in Silicon Photonics for Telecommunications and Biomedical Applications, B. Jalali and S. Fathpour, Eds., Taylor and Francis, London, UK, 2010.
[13]
R. W. Boyd, Nonlinear Optics, Academic Press, New York, NY, USA, 3rd edition, 2008.
[14]
L. Liu, R. Kumar, K. Huybrechts et al., “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nature Photonics, vol. 4, no. 3, pp. 182–187, 2010.
[15]
J. Hofrichter, F. Horst, N. Chrysos, et al., “Digital all-optical signal processing using microdisc lasers,” in Proceedings of the Optical Society of America, Conference on Integrated Photonics Research, Monterey, Calif, USA, July 2010, paper PTuA3.
[16]
P. Alipour, A. A. Eftekhar, A. H. Atabaki, et al., “Compact fully reconfigurable multi-stage RF photonic filters using high-Q silicon microdisk resonators,” in Proceedings of IEEE Photonics Society 7th Intl Conf on Group IV Photonics, Beijing, China, September 2010, paper FC6.
[17]
L. A. Coldren, “High performance photonic integrated circuits (PICs),” in Proceedings of the Optical Fiber Communications Conference, OSA/OFC/NFOEC, San Diego, Calif, USA, March 2010, tutorial OWD1.
[18]
A. Biberman, B. G. Lee, N. Sherwood-Droz, M. Lipson, and K. Bergman, “Broadband operation of nanophotonic router for silicon photonic networks-on-chip,” IEEE Photonics Technology Letters, vol. 22, no. 12, pp. 926–928, 2010.
[19]
K. Bergman, http://lightwave.ee.columbia.edu/?s=research&p=multi-processor_interconnection_networks.
[20]
A. Bianco, D. Cuda, R. Gaudino, G. Gavilanes, F. Neri, and M. Petracca, “Scalability of optical interconnects based on microring resonators,” IEEE Photonics Technology Letters, vol. 22, no. 15, Article ID 5464349, pp. 1081–1083, 2010.
[21]
S. Namiki, T. Hasama, and H. Ishikawa, “Energy bottlenecks in future networks and optical signal processing,” in Proceedings of the International Conference on Photonics in Switching, Pisa, Italy, Septemebr 2009, paper WeII1-1.
[22]
M. Florjańczyk, P. Cheben, S. Janz et al., “Slab waveguide spatial heterodyne spectrometers for remote sensing from space,” in Optical Sensors, vol. 7356 of Proceedings of SPIE, April 2009.
[23]
K. Okamoto, “Fourier-transform integrated-optic spatial heterodyne spectrometers based on planar lightwave circuits,” in Photonics in Switching, 2010, paper PWD3.
[24]
S. Dolev, “3rd International Workshop on Optical SuperComputing in Bertinoro,” http://www.cs.bgu.ac.il/~dolev/OSC10/.
[25]
J. Hardy and J. Shamir, “Optics inspired logic architecture,” Optics Express, vol. 15, no. 1, pp. 150–165, 2007.
[26]
L. Zhang, R. Ji, L. Yang, et al., “Simulation and demonstration of directed XOR logic gate using two cascaded microring resonators,” in Proceedings of the 7th International Conference on Group IV, Beijing, China, September 2010.
[27]
Q. Xu and R. Soref, “Reconfigurable optical directed-logic circuits using microresonator-based optical switches,” Optics Express, vol. 19, no. 6, pp. 5244–5259, 2011.
[28]
A. Peruzzo, M. Lobino, J. C. F. Matthews et al., “Quantum walks of correlated photons,” Science, vol. 329, no. 5998, pp. 1500–1503, 2010.
[29]
N. A. Riza and N. Madamopoulos, “Phased-array antenna, maximum-compression, reversible photonic beam former with ternary designs and multiple wavelengths,” Applied Optics, vol. 36, no. 5, pp. 983–996, 1997.
