The modulator is a key component in optical communications. Several graphene-based amplitude modulators have been reported based on electro-absorption. However, graphene phase modulators (GPMs) are necessary for functions such as applying complex modulation formats or making switches or phased arrays. Here, we present a 10 Gb s–1 GPM integrated in a Mach–Zehnder interferometer configuration. This is a compact device based on a graphene-insulator–silicon capacitor, with a phase-shifter length of 300 μm and extinction ratio of 35 dB. The GPM has a modulation efficiency of 0.28 V cm at 1,550 nm. It has 5 GHz electro-optical bandwidth and operates at 10 Gb s–1 with 2 V peak-to-peak driving voltage in a push–pull configuration for binary transmission of a non-return-to-zero data stream over 50 km of single-mode fibre. This device is the key building block for graphene-based integrated photonics, enabling compact and energy-efficient hybrid graphene–silicon modulators for telecom, datacom and other applications.
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Seimetz, M. High-Order Modulation for Optical Fiber Transmission (Springer Verlag, Berlin, Heidelberg, 2009).
Nakazawa, M., Kikuchi, K. & Miyazaki, T. High Spectral Density Optical Communication Technologies (Springer Verlag, Berlin, Heidelberg 2010).
Soref, R. & Bennet, B. Electro-optical effects in silicon. IEEE J. Quantum Electron. 23, 123–129 (1987).
Xiaotie, W. High Performance Optical Transmitter for Next Generation Supercomputing and Data Communication. PhD thesis 820, Univ. Pennsylvania (2013); http://repository.upenn.edu/edissertations/820
Abraham, A., Olivier, S., Marris-Morini, D. & Vivien, L. Evaluation of the performances of a silicon optical modulator based on a silicon-oxide-silicon capacitor. Proc. 11th International Conference on Group IV Photonics 3–4 (Paris, 2014).
Webster, M. A. et al. Low-power MOS-capacitor based silicon photonic modulators and CMOS drivers. Proc. 2015 Optical Fiber Communications Conference and Exhibition 1–3 (Los Angeles, 2015).
Xiong, C. et al. Monolithic 56 Gb/s silicon photonic pulse-amplitude modulation transmitter. Optica 3, 1060–1065 (2016).
Yu, H. et al. Performance tradeoff between lateral and interdigitated doping patterns for high speed carrier depletion based silicon modulators. Opt. Express 20, 12926–12938 (2012).
Wang, J. et al. Optimization and demonstration of a large-bandwidth carrier-depletion silicon optical modulator. J. Lightw. Technol. 31, 4119–4125 (2013).
Ding, J. et al. Ultra-low power carrier-depletion Mach–Zehnder silicon optical modulator. Opt. Express 20, 7081–7087 (2012).
Azadeh, S. et al. Advances in silicon photonics segmented electrode Mach–Zehnder modulators and peaking enhanced resonant devices. Proc. SPIE 9288, 928817 (2014).
Xiao, X. et al. High-speed, low-loss silicon Mach–Zehnder modulators with doping optimization. Opt. Express 21, 4116–4125 (2013).
Streshinsky, M. et al. Low power 50 Gb/s silicon traveling wave Mach–Zehnder modulator near 1300 nm. Opt. Express 21, 30350–30357 (2013).
Denoyer, G. et al. Hybrid silicon photonic circuits and transceiver for 50 Gb/s NRZ transmission over single-mode fiber. J. Lightw. Technol. 33, 1247–1254 (2015).
Reed, G. T. et al. Recent breakthroughs in carrier depletion based silicon optical modulators. Nanophotonics 3, 229–245 (2013).
Dong, P. et al. 50-Gb/s silicon quadrature phase-shift keying modulator. Opt. Express 20, 21181–21186 (2012).
Fresi, F. et al. Reconfigurable silicon photonics integrated 16-QAM modulator driven by binary electronics. IEEE J. Sel. Top. Quantum Electron. 22, 6100210 (2016).
Reed, G. T. Silicon Photonics: The State of the Art (Wiley, Chichester, 2008).
Miller, D. A. B. Energy consumption in optical modulators for interconnects. Opt. Express 20, A293–A308 (2012).
Grundmann, M. The Physics of Semiconductors: An Introduction Including Nanophysics and Applications, 2nd edn (Springer, 2010).
Han, J. H. et al. Effcient low-loss InGaAsP/Si hybrid MOS optical modulator. Nat. Photon. 11, 486–490 (2017).
Hiraki, T. et al. Heterogeneously integrated iii–v/Si MOS capacitor Mach–Zehnder modulator. Nat. Photon. 11, 482–485 (2017).
Bonaccorso, F., Sun, Z., Hasan, T. & Ferrari, A. C. Graphene photonics and optoelectronics. Nat. Photon. 4, 611–622 (2010).
Kim, K. et al. A role for graphene in silicon-based semiconductor devices. Nature 479, 338–344 (2011).
Ferrari, A. C. et al. Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems. Nanoscale 7, 4598–4810 (2015).
Castro Neto, A. H., Guinea, F., Peres, N. M. R., Novoselov, K. S. & Geim, A. K. The electronic properties of graphene. Rev. Mod. Phys. 81, 109 (2009).
Liu, M. et al. A graphene-based broadband optical modulator. Nature 474, 64–67 (2011).
Liu, M. et al. Double-layer graphene optical modulator. Nano Lett. 12, 1482–1485 (2012).
Hu, Y. et al. Broadband 10 Gb/s operation of graphene electro-absorption modulator on silicon. Laser Photon. Rev. 10, 307–316 (2016).
Phare, C. T. et al. Graphene electro-optic modulator with 30 GHz bandwidth. Nat. Photon. 9, 511–514 (2015).
Sorianello, V., Midrio, M. & Romagnoli, M. Design optimization of single and double layer graphene phase modulators in SOI. Opt. Express 23, 6478–6490 (2015).
Koppens, F. H. L. et al. Photodetectors based on graphene, other two-dimensional materials and hybrid hystems. Nat. Nanotech. 9, 780–793 (2014).
Goykhman, I. et al. On-chip integrated, silicon-graphene plasmonic Schottky photodetector, with high responsivity and avalanche photogain. Nano Lett. 16, 3005–3013 (2016).
Wang, F. et al. Gate-variable optical transitions in graphene. Science 320, 206–209 (2008).
Falkovsky, L. A. Optical properties of graphene. J. Phys. 129, 012004 (2008).
Stauber, T. et al. Optical conductivity of graphene in the visible region of the spectrum. Phys. Rev. B 78, 085432 (2008).
Yu, S. L. et al. 2D materials for optical modulation: challenges and opportunities. Adv. Mater. 29, 1606128 (2017).
Moshin, M. et al. Experimental verification of electro-refractive phase modulation in graphene. Sci. Rep. 5, 10967 (2015).
Sorianello, V. et al. Complex effective index in graphene–silicon waveguides. Opt. Express 24, 29984–29993 (2016).
Soldano, L. B. & Pennings, E. C. M. Optical multimode interference devices based on self-imaging: principles and applications. J. Lightw. Technol. 13, 615–627 (1995).
Roelkens, G. et al. High efficiency silicon-on-insulator grating coupler based on a poly-silicon overlay. Opt. Express 14, 11622–11630 (2006).
Banszerus, L. et al. Ultrahigh-mobility graphene devices from chemical vapor deposition on reusable copper. Sci. Adv. 1, e1500222 (2015).
Cançado, L. G. et al. Quantifying defects in graphene via Raman spectroscopy at different excitation energies. Nano Lett. 11, 3190–3196 (2011).
Bruna, M. et al. Doping dependence of the Raman spectrum of defected graphene. ACS Nano 8, 7432–7441 (2014).
Midrio, M., Galli, P., Romagnoli, M., Kimerling, L. C. & Michel, J. Graphene-based optical phase modulation of waveguide transverse electric modes. Photon. Res. 2, A34–A40 (2014).
Leong, W. S. et al. Low-contact resistance graphene devices with nickel-etched-graphene contacts. ACS Nano 8, 994–1001 (2014).
Tzimpragos, G. et al. A survey on FEC codes for 100G and beyond optical networks. IEEE Commun. Surv. Tut. 18, 209–221 (2016).
Absil, P. et al. Imec iSiPP25G silicon photonics: a robust CMOS-based photonics technology platform. Proc. SPIE 9367, 93670V (2015).
Li, B. X. et al. Large-area synthesis of high-quality and uniform graphene films on copper foils. Science 324, 1312–1314 (2009).
Zurutuza, A., Centeno, A., Alonso, B. & Pesquera, A. Method of manufacturing a graphene monolayer on insulating substrates. US patent 9,023,220 B2 (2015).
Ferrari, A. C. & Basko, D. M. Raman spectroscopy as a versatile tool for studying the properties of graphene. Nat. Nanotech. 8, 235–246 (2013).
Basko, D. M., Piscanec, S. & Ferrari, A. C. Electron–electron interactions and doping dependence of the two-phonon Raman intensity in graphene. Phys. Rev. B 80, 165413 (2009).
Das, A. et al. Monitoring dopants by Raman scattering in an electrochemically top-gated graphene transistor. Nat. Nanotech. 3, 210–215 (2008).
Lumerical Solutions, Inc; http://www.lumerical.com/tcad-products/device/
Hirai, H. et al. Electron mobility calculation for graphene on substrates. J. Appl. Phys. 116, 083703 (2014).
The authors acknowledge funding from the European Union Graphene Flagship Project, ERC Grant Hetero2D and EPSRC grant nos. EP/509 K01711X/1, EP/K017144/1, EP/N010345/1, EP/M507799/5101 and EP/L016087/1. The authors also acknowledge Graphenea for the provision of CVD graphene samples.
The authors declare no competing financial interests.
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Sorianello, V., Midrio, M., Contestabile, G. et al. Graphene–silicon phase modulators with gigahertz bandwidth. Nature Photon 12, 40–44 (2018). https://doi.org/10.1038/s41566-017-0071-6
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