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Graphene–silicon phase modulators with gigahertz bandwidth

Abstract

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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Fig. 1: Device.
Fig. 2: Raman characterization.
Fig. 3: Static electro-optical characterization.
Fig. 4: Dynamic characterization.
Fig. 5: Transmission measurements.

References

  1. 1.

    Seimetz, M. High-Order Modulation for Optical Fiber Transmission (Springer Verlag, Berlin, Heidelberg, 2009).

    Book  Google Scholar 

  2. 2.

    Nakazawa, M., Kikuchi, K. & Miyazaki, T. High Spectral Density Optical Communication Technologies (Springer Verlag, Berlin, Heidelberg 2010).

    Book  Google Scholar 

  3. 3.

    Soref, R. & Bennet, B. Electro-optical effects in silicon. IEEE J. Quantum Electron. 23, 123–129 (1987).

    ADS  Article  Google Scholar 

  4. 4.

    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

  5. 5.

    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).

  6. 6.

    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).

  7. 7.

    Xiong, C. et al. Monolithic 56 Gb/s silicon photonic pulse-amplitude modulation transmitter. Optica 3, 1060–1065 (2016).

    Article  Google Scholar 

  8. 8.

    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).

    ADS  Article  Google Scholar 

  9. 9.

    Wang, J. et al. Optimization and demonstration of a large-bandwidth carrier-depletion silicon optical modulator. J. Lightw. Technol. 31, 4119–4125 (2013).

    ADS  Article  Google Scholar 

  10. 10.

    Ding, J. et al. Ultra-low power carrier-depletion Mach–Zehnder silicon optical modulator. Opt. Express 20, 7081–7087 (2012).

    ADS  Article  Google Scholar 

  11. 11.

    Azadeh, S. et al. Advances in silicon photonics segmented electrode Mach–Zehnder modulators and peaking enhanced resonant devices. Proc. SPIE 9288, 928817 (2014).

    Google Scholar 

  12. 12.

    Xiao, X. et al. High-speed, low-loss silicon Mach–Zehnder modulators with doping optimization. Opt. Express 21, 4116–4125 (2013).

    ADS  Article  Google Scholar 

  13. 13.

    Streshinsky, M. et al. Low power 50 Gb/s silicon traveling wave Mach–Zehnder modulator near 1300 nm. Opt. Express 21, 30350–30357 (2013).

    ADS  Article  Google Scholar 

  14. 14.

    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).

    ADS  Article  Google Scholar 

  15. 15.

    Reed, G. T. et al. Recent breakthroughs in carrier depletion based silicon optical modulators. Nanophotonics 3, 229–245 (2013).

    Google Scholar 

  16. 16.

    Dong, P. et al. 50-Gb/s silicon quadrature phase-shift keying modulator. Opt. Express 20, 21181–21186 (2012).

    ADS  Article  Google Scholar 

  17. 17.

    Fresi, F. et al. Reconfigurable silicon photonics integrated 16-QAM modulator driven by binary electronics. IEEE J. Sel. Top. Quantum Electron. 22, 6100210 (2016).

    Article  Google Scholar 

  18. 18.

    Reed, G. T. Silicon Photonics: The State of the Art (Wiley, Chichester, 2008).

  19. 19.

    Miller, D. A. B. Energy consumption in optical modulators for interconnects. Opt. Express 20, A293–A308 (2012).

    ADS  Article  Google Scholar 

  20. 20.

    Grundmann, M. The Physics of Semiconductors: An Introduction Including Nanophysics and Applications, 2nd edn (Springer, 2010).

  21. 21.

    Han, J. H. et al. Effcient low-loss InGaAsP/Si hybrid MOS optical modulator. Nat. Photon. 11, 486–490 (2017).

    Article  Google Scholar 

  22. 22.

    Hiraki, T. et al. Heterogeneously integrated iii–v/Si MOS capacitor Mach–Zehnder modulator. Nat. Photon. 11, 482–485 (2017).

    Article  Google Scholar 

  23. 23.

    Bonaccorso, F., Sun, Z., Hasan, T. & Ferrari, A. C. Graphene photonics and optoelectronics. Nat. Photon. 4, 611–622 (2010).

    ADS  Article  Google Scholar 

  24. 24.

    Kim, K. et al. A role for graphene in silicon-based semiconductor devices. Nature 479, 338–344 (2011).

    ADS  Article  Google Scholar 

  25. 25.

    Ferrari, A. C. et al. Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems. Nanoscale 7, 4598–4810 (2015).

    ADS  Article  Google Scholar 

  26. 26.

    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).

    ADS  Article  Google Scholar 

  27. 27.

    Liu, M. et al. A graphene-based broadband optical modulator. Nature 474, 64–67 (2011).

    ADS  Article  Google Scholar 

  28. 28.

    Liu, M. et al. Double-layer graphene optical modulator. Nano Lett. 12, 1482–1485 (2012).

    ADS  Article  Google Scholar 

  29. 29.

    Hu, Y. et al. Broadband 10 Gb/s operation of graphene electro-absorption modulator on silicon. Laser Photon. Rev. 10, 307–316 (2016).

    Article  Google Scholar 

  30. 30.

    Phare, C. T. et al. Graphene electro-optic modulator with 30 GHz bandwidth. Nat. Photon. 9, 511–514 (2015).

    ADS  Article  Google Scholar 

  31. 31.

    Sorianello, V., Midrio, M. & Romagnoli, M. Design optimization of single and double layer graphene phase modulators in SOI. Opt. Express 23, 6478–6490 (2015).

    ADS  Article  Google Scholar 

  32. 32.

    Koppens, F. H. L. et al. Photodetectors based on graphene, other two-dimensional materials and hybrid hystems. Nat. Nanotech. 9, 780–793 (2014).

    ADS  Article  Google Scholar 

  33. 33.

    Goykhman, I. et al. On-chip integrated, silicon-graphene plasmonic Schottky photodetector, with high responsivity and avalanche photogain. Nano Lett. 16, 3005–3013 (2016).

    ADS  Article  Google Scholar 

  34. 34.

    Wang, F. et al. Gate-variable optical transitions in graphene. Science 320, 206–209 (2008).

    ADS  Article  Google Scholar 

  35. 35.

    Falkovsky, L. A. Optical properties of graphene. J. Phys. 129, 012004 (2008).

    Google Scholar 

  36. 36.

    Stauber, T. et al. Optical conductivity of graphene in the visible region of the spectrum. Phys. Rev. B 78, 085432 (2008).

    ADS  Article  Google Scholar 

  37. 37.

    Yu, S. L. et al. 2D materials for optical modulation: challenges and opportunities. Adv. Mater. 29, 1606128 (2017).

    Article  Google Scholar 

  38. 38.

    Moshin, M. et al. Experimental verification of electro-refractive phase modulation in graphene. Sci. Rep. 5, 10967 (2015).

    ADS  Article  Google Scholar 

  39. 39.

    Sorianello, V. et al. Complex effective index in graphene–silicon waveguides. Opt. Express 24, 29984–29993 (2016).

    ADS  Article  Google Scholar 

  40. 40.

    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).

    ADS  Article  Google Scholar 

  41. 41.

    Roelkens, G. et al. High efficiency silicon-on-insulator grating coupler based on a poly-silicon overlay. Opt. Express 14, 11622–11630 (2006).

    ADS  Article  Google Scholar 

  42. 42.

    Banszerus, L. et al. Ultrahigh-mobility graphene devices from chemical vapor deposition on reusable copper. Sci. Adv. 1, e1500222 (2015).

    ADS  Article  Google Scholar 

  43. 43.

    Cançado, L. G. et al. Quantifying defects in graphene via Raman spectroscopy at different excitation energies. Nano Lett. 11, 3190–3196 (2011).

    ADS  Article  Google Scholar 

  44. 44.

    Bruna, M. et al. Doping dependence of the Raman spectrum of defected graphene. ACS Nano 8, 7432–7441 (2014).

    Article  Google Scholar 

  45. 45.

    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).

    Article  Google Scholar 

  46. 46.

    Leong, W. S. et al. Low-contact resistance graphene devices with nickel-etched-graphene contacts. ACS Nano 8, 994–1001 (2014).

    Article  Google Scholar 

  47. 47.

    Tzimpragos, G. et al. A survey on FEC codes for 100G and beyond optical networks. IEEE Commun. Surv. Tut. 18, 209–221 (2016).

    Article  Google Scholar 

  48. 48.

    Absil, P. et al. Imec iSiPP25G silicon photonics: a robust CMOS-based photonics technology platform. Proc. SPIE 9367, 93670V (2015). 

  49. 49.

    Li, B. X. et al. Large-area synthesis of high-quality and uniform graphene films on copper foils. Science 324, 1312–1314 (2009).

    ADS  Article  Google Scholar 

  50. 50.

    Zurutuza, A., Centeno, A., Alonso, B. & Pesquera, A. Method of manufacturing a graphene monolayer on insulating substrates. US patent 9,023,220 B2 (2015).

  51. 51.

    Ferrari, A. C. & Basko, D. M. Raman spectroscopy as a versatile tool for studying the properties of graphene. Nat. Nanotech. 8, 235–246 (2013).

    ADS  Article  Google Scholar 

  52. 52.

    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).

    ADS  Article  Google Scholar 

  53. 53.

    Das, A. et al. Monitoring dopants by Raman scattering in an electrochemically top-gated graphene transistor. Nat. Nanotech. 3, 210–215 (2008).

    Article  Google Scholar 

  54. 54.

    Lumerical Solutions, Inc; http://www.lumerical.com/tcad-products/device/

  55. 55.

    Hirai, H. et al. Electron mobility calculation for graphene on substrates. J. Appl. Phys. 116, 083703 (2014).

    ADS  Article  Google Scholar 

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Acknowledgements

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.

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All authors conceived the phase modulator within the Graphene Flagship project. V.S., M.M., G.C. and M.R. carried out device design and testing. I.A., J.V.C. and C.H. fabricated the device. I.G., A.K.O. and A.C.F. performed material characterization.

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Correspondence to M. Romagnoli.

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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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