We propose using a hydrogenated amorphous silicon waveguide for ultra-high-speed serial data waveform sampling. 320 Gbit/s serial optical data sampling is experimentally demonstrated with +12 dB intrinsic four wave mixing conversion efficiency

Baets, Roel

Galili, M.

Hu, H.

Jeppesen, P.

Ji, H.

Kuyken, Bart

Morthier, Geert

Oxenlowe, L. K.

Pu, M.

Selvaraja, shankar kumar

English

Ghent University Academic Bibliography

Optical Waveform Sampling of a 320 Gbit/s Serial Data Signal using a Hydrogenated Amorphous Silicon Waveguide  H. Ji1, H. Hu1, M. Pu1, M. Galili1, P. Jeppesen1, B. Kuyken2, S. K. Selvaraja2, G. Morthier2, R. Baets2 and L.K. Oxenløwe11DTU Fotonik, Technical University of Denmark, Building 343, DK-2800 Kgs. Lyngby, Denmark 2Photonics Research Group, INTEC Department, Ghent University—imec, Sint-Pietersnieuwstraat 41, 9000 Ghent, Belgium huji@fotonik.dtu.dk Abstract: We propose using a hydrogenated amorphous silicon waveguide for ultra-high-speed serial data waveform sampling. 320 Gbit/s serial optical data sampling is experimentally demonstrated with +12 dB intrinsic four wave mixing conversion efficiency.   OCIS codes: (230.7370) Waveguides; (070.4340) Nonlinear optical signal processing; (070.7145) Ultrafast processing.  1. Introduction Silicon based optical signal processing has attracted considerable research interest in recent years, due to its complementary metal-oxide-semiconductor (CMOS) compatibility, low cost, ultra-compactness, broad working bandwidth and high-speed operation. Crystalline silicon (c-Si) waveguides have been studied extensively and various high speed optical signal processing have been realized by using c-Si waveguides, such as four wave mixing (FWM) based 10 Gbit/s signal regeneration [1], 160 Gbit/s demultiplexing and wavelength conversion [2,3], 1.28 Tbit/s waveform sampling and demultiplexing [4], and 640 Gbit/s wavelength conversion [5]. However, all these c-Si based signal processing suffer from the nonlinear two photon absorption (TPA) and slow dynamics of TPA induced free carrier absorption (FCA). The TPA in c-Si waveguides can not be avoided at the telecommunication wavelengths of 1550 nm. Therefore, the FWM conversion efficiency is heavily limited by the TPA and FCA. Several methods have been proposed to overcome this problem [6, 7]. However, these realizations suffer either from lower linear and nonlinear refractive indices or from incompatibility with CMOS fabrication. Silicon-on-insulator (SOI) waveguides with a hydrogenated amorphous silicon (a-Si:H) waveguide core are an alternative to the standard crystalline SOI high-index contrast waveguide platform. Because a-Si:H is a material with considerable freedom in chemical structure, different fabrication procedures can give rise to different material properties, including the bandgap. Therefore, it is possible to fabricate a-Si:H waveguides with low TPA at telecommunication wavelengths while maintaining the high nonlinearity. Recently a parametric on-off gain of + 26 dB was demonstrated in these waveguides [8].          In this paper, we will demonstrate an a-Si:H waveguide based 320 Gbit/s serial data signal waveform sampling system. In the demonstration, a +12 dB intrinsic conversion efficiency is achieved, which is 19.5 dB higher than previously obtained results in c-Si:H waveguides [4].  2. Characterization of the a-Si:H waveguide  The a-Si:H waveguide used in this experiment is 4 mm long and its cross-sectional dimensions are 220 nm × 500nm, as shown in Fig. 1 (Left). The propagation loss is about 3.6 dB/cm. Diffractive grating couplers are used to couple the light between fibers and the device. Fig. 1 (Right) shows the insertion loss of this waveguide, including coupling loss and propagation loss. The insertion loss ranges from 13 to 18 dB, depending on the wavelength used in the experiment.  1530 1540 1550 1560 1570 1580-24-23-22-21-20-19-18-17-16-15-14-13-12Insertion loss [dB]Wavelength [nm]500 nm220 nma-Si:HSiO2 Fig. 1. (Left) The cross section of the a-Si:H waveguide, pictured using a scanning electron microscope, (Right) Measured insertion loss as function of wavelength.       The waveguide is built in 220-nm-thick hydrogenated amorphous silicon deposited on top of a 1950-nm-thick polished high-density silicon dioxide layer. The 220-nm thick a-Si:H film is deposited by plasma-enhanced chemical vapor deposition (PECVD). The film was formed using silane (SiH4) as a precursor gas along with helium (He) dilution. Low losses can be achieved by optimizing several parameters, such as the gas ratio (He/SiH4) and the plasma power [9]. After forming the waveguide core layer, 500-nm-wide photonic wires were patterned using CMOS fabrication technology. The bandgap of a-Si:H films is measured to be 1.61 eV, by using spectroscopic ellipsometry (in the 300–1600nm range) [8], while c-Si has a bandgap of 1.12 eV. Therefore, the half-bandgap of a-Si:H is approximately 0.805 eV, corresponding to λ = 1540 nm. This half-bandgap will dramatically decrease the TPA in the a-Si:H waveguide when the wavelength is longer than 1540 nm, and thus improve the FWM conversion efficiency. 3. Experimental setup The experimental scheme of a-Si:H based optical sampling is shown in Fig. 2. A fiber ring mode-locked laser is used as the sampling source, which uses a 30 cm erbium-doped fiber as gain medium and carbon nanotubes (CNT) as the mode-locker [10].The generated sampling pulses have a repetition rate of  16.3 MHz and a squared hyperbolic secant shape with ~ 710 fs FWHM, measured using an autocorrelator directly at the laser output. The central wavelength of the pulses is at 1558 nm and has a 4 nm 3-dB spectral bandwidth. To avoid serious spectral broadening due to self-phase modulation (SPM) in the highly nonlinear a-Si:H waveguide, the sampling pulse is broadened to 1.4 ps by adding 10 m single mode fiber (SMF). The 320 Gbit/s serial data signal is generated using the Optical Time Division Multiplexing (OTDM) technique. An erbium glass oscillator (ERGO) optical pulse source generates a 10 GHz pulse train at 1550 nm with 2 ps FWHM. After amplification in an EDFA, the 10 GHz data pulses are sent into a dispersion flattened highly nonlinear fiber (DF-HNLF) to broaden the spectrum. Then a 5 nm bandpass filter is used to filter out part of the spectrum. The pulse width of the 10 GHz pulses is compressed to 1 ps in this way. A Mach-Zender modulator encodes a 10 Gbit/s on-off keying (OOK) data sequence (PRBS 27-1) on the pulse train and the 10 Gbit/s data signal is multiplexed to 320 Gbit/s by a passive fiber delay PRBS and polarization maintaining multiplexer (MUX). The 320 Gbit/s OTDM OOK data signal is coupled into the a-Si:H waveguide together with the sampling pulse train. The polarization states into the a-Si:H waveguide of the data signal and the sampling pulse are aligned to the TE mode by polarization controllers. The data signal power and sampling pulses power before coupling into the a-Si:H waveguide is 5 dBm and -5 dBm respectively. In the a-Si:H waveguide, FWM will take place when the sampling pulses (pump) overlap with the data pulses (signal) and generate a new FWM product (idler). After the a-Si:H waveguide, the FWM product is selected by L-band filters and directly detected using a high sensitivity photo-detector (with 200 MHz bandwidth). To observe the waveform on the 1 Gsample/s oscilloscope (with 350 MHz bandwidth), the sampling pulse itself is used as a gate trigger for the oscilloscope and the sampling frequency is fine-tuned to ensure the correct temporal order of the samples.  Fig. 2. The experimental setup of the a-Si:H waveguide based optical sampling system 4. Experimental results  The 320 Gbit/s OTDM OOK data is successfully sampled using this a-Si:H based sampling system. Fig. 3 (Left) shows a clear open eye-diagram measured with the constructed system. Furthermore, the pulse width of the sampled data pulse is measured to be 1.3 ps. Compared to the pulse width of 1 ps measured using an autocorrelator, the sampled pulses are wider than the real pulse width when using the a-Si:H based optical sampling process. This broadening is caused by the sampling time resolution, which is limited by the sampling pulse width and the walk-off between the sampling and sampled pulses. The time resolution of this a-Si:H based sampling system is estimated, by deconvolving from the actual pulse width (measured with autocorrelator) [11], to Δτ=((1.3 ps)2-(1 ps)2)1/2≈0.830 ps. This time resolution could be further improved by using narrower sampling pulses. 1510 1520 1530 1540 1550 1560 1570 1580 1590 1600-90-80-70-60-50-40-30-20  Power [dBm/0.1nm]Wavelength [nm]1520 1530 1540 1550 1560 1570 1580 1590-80-70-60-50-40-30-20-10 FWM productPump only Pump after silicon after silicon before silicon  Power [dBm/0.1nm]Wavelength [nm]Data signal Fig. 3. (Left) Sampled eye-diagram of the 320 Gbit/s serial data signal using the a-Si:H based optical sampling system, (Middle) Measured optical spectra before and after the a-Si:H waveguide, (Right) Spectrum of data signal and FWM product at output of waveguide when subtracting the pump. Fig. 3 (Middle) is the measured spectra during the sampling process. Comparing to the input pump spectrum, the output is broadened, as shown in curve ‘only Pump after silicon’. This broadening is caused by SPM in the a-Si:H waveguide. Fig. 3 (Right) shows the spectra of the data signal and FWM product at the output of the waveguide. Here, the pump only spectrum is subtracted. To calculate the FWM conversion efficiency in the a-Si:H waveguid, the output power of the data signal and FWM product are measured to Pdata_out = - 14.5 dBm and PFWM_out = - 44 dBm, respectively, by integrating the spectrum shown in Fig. 3 (Right). Here we define the intrinsic conversion efficiency as the ratio between the FWM product power just before it is coupled out from the a-Si:H waveguide and the data signal power coupled into the a-Si:H waveguide. Therefore the intrinsic conversion efficiency is expressed as  ηIntrinsic = (PFWM_out+lcoupling) - (Pdata_out+lcoupling+l) Where lcoupling is the coupling loss between fiber and waveguide, and l is the propagation loss of the waveguide which is 1.5 dB for this a-Si:H waveguide. Moreover, considering the duty cycle between sampling pulses and the data signal (43 dB here), the intrinsic conversion efficiency amounts to +12 dB. In a similar optical sampling system based on c-Si [4], the intrinsic conversion efficiency is -7.5 dB. This 19.5 dB improvement on intrinsic conversion efficiency is believed a benefit from the much lower TPA in the a-Si:H waveguide compared to the c-Si waveguide at the wavelengths longer than 1540 nm.  5. Conclusion  We have successfully demonstrated a 320 Gbit/s serial data signal waveform sampling using an a-Si:H waveguide. The sampling system has a temporal resolution of 830 fs and intrinsic conversion efficiency of +12 dB. This result shows that the a-Si:H waveguide has a promising potential for ultra-high-speed nonlinear optical signal processing.  6. Reference  [1] R. Salem, et al., “Signal regeneration using low power four-wave mixing on silicon chip,” Nature Photonics 2, 35–38 (2008). [2] F. Li, et al., “Error-free all-optical demultiplexing at 160Gb/s via FWM in a silicon nanowire,” Optical Express, Vol. 18, No. 4, 3905(2010) [3] N. Ophir, et al., “First 80-Gb/s and 160-Gb/s wavelength converted data stream measurements in a silicon waveguide,” OFC 2010, OWP5, (2010). [4] H. Ji, et al, “1.28 Tbit/s OTDM-OOK Data Waveform Sampling and Demultiplexing Using Silicon Nano-wire,” OFC 2010, paper PDPC7. [5] H. Hu et al., “Silicon Chip based Wavelength Conversion of Ultra-High Repetition Rate Data Signals”, OFC 2011, paper PDPA8. [6] C. Koos, et al, “All-optical high-speed signal processing with silicon–organic hybrid slot waveguides”, Nature Photonics, 3, 216 (2009). [7] J. S. Levy, et al, “CMOS-compatible multiple-wavelength oscillator for on-chip optical interconnects”, Nature Photonics, 4, 37 (2009). [8] B. Kuyken, et al, “On-chip parametric amplification with 26:5 dB gain at telecommunication wavelengths using CMOS-compatible hydrogenated amorphous silicon waveguides”, Optics Letters, 36,4, 552-, (2011) [9] S. Selvaraja, et al, “Low-Loss Amorphous Silicon-On-Insulator Technology for Photonic Integrated Circuitry”, Optics Communications, 282(9), p. 1767-1770 (2009). [10] H. Ji, et al, “Fiber Optical Trap Deposition of Carbon Nanotubes on Fiber End-faces in a Modelocked Laser”, CLEO’08, CtuV4, (2008). [11] P. A. Andrekson,et al, “Nonlinear optical fiber based high resolution all-optical waveform sampling,” Laser and photonics reviews, No. 3, 231–248 (2007). 

Optical waveform sampling of a 320 Gbits/s serial data signal using a hydrogenated amorphous silicon waveguide

Ji, Hua

Hu, Hao

Pu, Minhao

Galili, Michael

Jeppesen, Palle

Kuyken, B.

Selvaraja, S. K.

Morthier, G.

Baets, R.

Oxenløwe, Leif Katsuo

Online Research Database In Technology

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Downloaded from orbit.dtu.dk on: Dec 19, 2017Optical Waveform Sampling of a 320 Gbit/s Serial Data Signal using a HydrogenatedAmorphous Silicon WaveguideJi, Hua; Hu, Hao; Pu, Minhao; Galili, Michael; Jeppesen, Palle; Kuyken, B.; Selvaraja, S. K.; Morthier, G.;Baets, R.; Oxenløwe, Leif KatsuoPublished in:Proceedings of the European Conference on Optical Communication (ECOC) 2011Publication date:2011Document VersionPublisher's PDF, also known as Version of recordLink back to DTU OrbitCitation (APA):Ji, H., Hu, H., Pu, M., Galili, M., Jeppesen, P., Kuyken, B., ... Oxenløwe, L. K. (2011). Optical WaveformSampling of a 320 Gbit/s Serial Data Signal using a Hydrogenated Amorphous Silicon Waveguide. InProceedings of the European Conference on Optical Communication (ECOC) 2011Optical Waveform Sampling of a 320 Gbit/s Serial Data Signal using a Hydrogenated Amorphous Silicon Waveguide  H. Ji1, H. Hu1, M. Pu1, M. Galili1, P. Jeppesen1, B. Kuyken2, S. K. Selvaraja2, G. Morthier2, R. Baets2 and L.K. Oxenløwe11DTU Fotonik, Technical University of Denmark, Building 343, DK-2800 Kgs. Lyngby, Denmark 2Photonics Research Group, INTEC Department, Ghent University—imec, Sint-Pietersnieuwstraat 41, 9000 Ghent, Belgium huji@fotonik.dtu.dk Abstract: We propose using a hydrogenated amorphous silicon waveguide for ultra-high-speed serial data waveform sampling. 320 Gbit/s serial optical data sampling is experimentally demonstrated with +12 dB intrinsic four wave mixing conversion efficiency.   OCIS codes: (230.7370) Waveguides; (070.4340) Nonlinear optical signal processing; (070.7145) Ultrafast processing.  1. Introduction Silicon based optical signal processing has attracted considerable research interest in recent years, due to its complementary metal-oxide-semiconductor (CMOS) compatibility, low cost, ultra-compactness, broad working bandwidth and high-speed operation. Crystalline silicon (c-Si) waveguides have been studied extensively and various high speed optical signal processing have been realized by using c-Si waveguides, such as four wave mixing (FWM) based 10 Gbit/s signal regeneration [1], 160 Gbit/s demultiplexing and wavelength conversion [2,3], 1.28 Tbit/s waveform sampling and demultiplexing [4], and 640 Gbit/s wavelength conversion [5]. However, all these c-Si based signal processing suffer from the nonlinear two photon absorption (TPA) and slow dynamics of TPA induced free carrier absorption (FCA). The TPA in c-Si waveguides can not be avoided at the telecommunication wavelengths of 1550 nm. Therefore, the FWM conversion efficiency is heavily limited by the TPA and FCA. Several methods have been proposed to overcome this problem [6, 7]. However, these realizations suffer either from lower linear and nonlinear refractive indices or from incompatibility with CMOS fabrication. Silicon-on-insulator (SOI) waveguides with a hydrogenated amorphous silicon (a-Si:H) waveguide core are an alternative to the standard crystalline SOI high-index contrast waveguide platform. Because a-Si:H is a material with considerable freedom in chemical structure, different fabrication procedures can give rise to different material properties, including the bandgap. Therefore, it is possible to fabricate a-Si:H waveguides with low TPA at telecommunication wavelengths while maintaining the high nonlinearity. Recently a parametric on-off gain of + 26 dB was demonstrated in these waveguides [8].          In this paper, we will demonstrate an a-Si:H waveguide based 320 Gbit/s serial data signal waveform sampling system. In the demonstration, a +12 dB intrinsic conversion efficiency is achieved, which is 19.5 dB higher than previously obtained results in c-Si:H waveguides [4].  2. Characterization of the a-Si:H waveguide  The a-Si:H waveguide used in this experiment is 4 mm long and its cross-sectional dimensions are 220 nm × 500nm, as shown in Fig. 1 (Left). The propagation loss is about 3.6 dB/cm. Diffractive grating couplers are used to couple the light between fibers and the device. Fig. 1 (Right) shows the insertion loss of this waveguide, including coupling loss and propagation loss. The insertion loss ranges from 13 to 18 dB, depending on the wavelength used in the experiment.  1530 1540 1550 1560 1570 1580-24-23-22-21-20-19-18-17-16-15-14-13-12Insertion loss [dB]Wavelength [nm]500 nm220 nma-Si:HSiO2 Fig. 1. (Left) The cross section of the a-Si:H waveguide, pictured using a scanning electron microscope, (Right) Measured insertion loss as function of wavelength. Th.11.LeSaleve.1.pdf   1 7/27/2011   4:21:49 PMECOC Technical Digest © 2011 OSA      The waveguide is built in 220-nm-thick hydrogenated amorphous silicon deposited on top of a 1950-nm-thick polished high-density silicon dioxide layer. The 220-nm thick a-Si:H film is deposited by plasma-enhanced chemical vapor deposition (PECVD). The film was formed using silane (SiH4) as a precursor gas along with helium (He) dilution. Low losses can be achieved by optimizing several parameters, such as the gas ratio (He/SiH4) and the plasma power [9]. After forming the waveguide core layer, 500-nm-wide photonic wires were patterned using CMOS fabrication technology. The bandgap of a-Si:H films is measured to be 1.61 eV, by using spectroscopic ellipsometry (in the 300–1600nm range) [8], while c-Si has a bandgap of 1.12 eV. Therefore, the half-bandgap of a-Si:H is approximately 0.805 eV, corresponding to λ = 1540 nm. This half-bandgap will dramatically decrease the TPA in the a-Si:H waveguide when the wavelength is longer than 1540 nm, and thus improve the FWM conversion efficiency. 3. Experimental setup The experimental scheme of a-Si:H based optical sampling is shown in Fig. 2. A fiber ring mode-locked laser is used as the sampling source, which uses a 30 cm erbium-doped fiber as gain medium and carbon nanotubes (CNT) as the mode-locker [10].The generated sampling pulses have a repetition rate of  16.3 MHz and a squared hyperbolic secant shape with ~ 710 fs FWHM, measured using an autocorrelator directly at the laser output. The central wavelength of the pulses is at 1558 nm and has a 4 nm 3-dB spectral bandwidth. To avoid serious spectral broadening due to self-phase modulation (SPM) in the highly nonlinear a-Si:H waveguide, the sampling pulse is broadened to 1.4 ps by adding 10 m single mode fiber (SMF). The 320 Gbit/s serial data signal is generated using the Optical Time Division Multiplexing (OTDM) technique. An erbium glass oscillator (ERGO) optical pulse source generates a 10 GHz pulse train at 1550 nm with 2 ps FWHM. After amplification in an EDFA, the 10 GHz data pulses are sent into a dispersion flattened highly nonlinear fiber (DF-HNLF) to broaden the spectrum. Then a 5 nm bandpass filter is used to filter out part of the spectrum. The pulse width of the 10 GHz pulses is compressed to 1 ps in this way. A Mach-Zender modulator encodes a 10 Gbit/s on-off keying (OOK) data sequence (PRBS 27-1) on the pulse train and the 10 Gbit/s data signal is multiplexed to 320 Gbit/s by a passive fiber delay PRBS and polarization maintaining multiplexer (MUX). The 320 Gbit/s OTDM OOK data signal is coupled into the a-Si:H waveguide together with the sampling pulse train. The polarization states into the a-Si:H waveguide of the data signal and the sampling pulse are aligned to the TE mode by polarization controllers. The data signal power and sampling pulses power before coupling into the a-Si:H waveguide is 5 dBm and -5 dBm respectively. In the a-Si:H waveguide, FWM will take place when the sampling pulses (pump) overlap with the data pulses (signal) and generate a new FWM product (idler). After the a-Si:H waveguide, the FWM product is selected by L-band filters and directly detected using a high sensitivity photo-detector (with 200 MHz bandwidth). To observe the waveform on the 1 Gsample/s oscilloscope (with 350 MHz bandwidth), the sampling pulse itself is used as a gate trigger for the oscilloscope and the sampling frequency is fine-tuned to ensure the correct temporal order of the samples.  Fig. 2. The experimental setup of the a-Si:H waveguide based optical sampling system 4. Experimental results  The 320 Gbit/s OTDM OOK data is successfully sampled using this a-Si:H based sampling system. Fig. 3 (Left) shows a clear open eye-diagram measured with the constructed system. Furthermore, the pulse width of the sampled data pulse is measured to be 1.3 ps. Compared to the pulse width of 1 ps measured using an autocorrelator, the sampled pulses are wider than the real pulse width when using the a-Si:H based optical sampling process. This broadening is caused by the sampling time resolution, which is limited by the sampling pulse width and the walk-off between the sampling and sampled pulses. The time resolution of this a-Si:H based sampling system is estimated, by deconvolving from the actual pulse width (measured with autocorrelator) [11], to Δτ=((1.3 ps)2-(1 ps)2)1/2≈0.830 ps. This time resolution could be further improved by using narrower sampling pulses. Th.11.LeSaleve.1.pdf   2 7/27/2011   4:21:49 PMECOC Technical Digest © 2011 OSA1510 1520 1530 1540 1550 1560 1570 1580 1590 1600-90-80-70-60-50-40-30-20  Power [dBm/0.1nm]Wavelength [nm]1520 1530 1540 1550 1560 1570 1580 1590-80-70-60-50-40-30-20-10 FWM productPump only Pump after silicon after silicon before silicon  Power [dBm/0.1nm]Wavelength [nm]Data signal Fig. 3. (Left) Sampled eye-diagram of the 320 Gbit/s serial data signal using the a-Si:H based optical sampling system, (Middle) Measured optical spectra before and after the a-Si:H waveguide, (Right) Spectrum of data signal and FWM product at output of waveguide when subtracting the pump. Fig. 3 (Middle) is the measured spectra during the sampling process. Comparing to the input pump spectrum, the output is broadened, as shown in curve ‘only Pump after silicon’. This broadening is caused by SPM in the a-Si:H waveguide. Fig. 3 (Right) shows the spectra of the data signal and FWM product at the output of the waveguide. Here, the pump only spectrum is subtracted. To calculate the FWM conversion efficiency in the a-Si:H waveguid, the output power of the data signal and FWM product are measured to Pdata_out = - 14.5 dBm and PFWM_out = - 44 dBm, respectively, by integrating the spectrum shown in Fig. 3 (Right). Here we define the intrinsic conversion efficiency as the ratio between the FWM product power just before it is coupled out from the a-Si:H waveguide and the data signal power coupled into the a-Si:H waveguide. Therefore the intrinsic conversion efficiency is expressed as  ηIntrinsic = (PFWM_out+lcoupling) - (Pdata_out+lcoupling+l) Where lcoupling is the coupling loss between fiber and waveguide, and l is the propagation loss of the waveguide which is 1.5 dB for this a-Si:H waveguide. Moreover, considering the duty cycle between sampling pulses and the data signal (43 dB here), the intrinsic conversion efficiency amounts to +12 dB. In a similar optical sampling system based on c-Si [4], the intrinsic conversion efficiency is -7.5 dB. This 19.5 dB improvement on intrinsic conversion efficiency is believed a benefit from the much lower TPA in the a-Si:H waveguide compared to the c-Si waveguide at the wavelengths longer than 1540 nm.  5. Conclusion  We have successfully demonstrated a 320 Gbit/s serial data signal waveform sampling using an a-Si:H waveguide. The sampling system has a temporal resolution of 830 fs and intrinsic conversion efficiency of +12 dB. This result shows that the a-Si:H waveguide has a promising potential for ultra-high-speed nonlinear optical signal processing.  6. Reference  [1] R. Salem, et al., “Signal regeneration using low power four-wave mixing on silicon chip,” Nature Photonics 2, 35–38 (2008). [2] F. Li, et al., “Error-free all-optical demultiplexing at 160Gb/s via FWM in a silicon nanowire,” Optical Express, Vol. 18, No. 4, 3905(2010) [3] N. Ophir, et al., “First 80-Gb/s and 160-Gb/s wavelength converted data stream measurements in a silicon waveguide,” OFC 2010, OWP5, (2010). [4] H. Ji, et al, “1.28 Tbit/s OTDM-OOK Data Waveform Sampling and Demultiplexing Using Silicon Nano-wire,” OFC 2010, paper PDPC7. [5] H. Hu et al., “Silicon Chip based Wavelength Conversion of Ultra-High Repetition Rate Data Signals”, OFC 2011, paper PDPA8. [6] C. Koos, et al, “All-optical high-speed signal processing with silicon–organic hybrid slot waveguides”, Nature Photonics, 3, 216 (2009). [7] J. S. Levy, et al, “CMOS-compatible multiple-wavelength oscillator for on-chip optical interconnects”, Nature Photonics, 4, 37 (2009). [8] B. Kuyken, et al, “On-chip parametric amplification with 26:5 dB gain at telecommunication wavelengths using CMOS-compatible hydrogenated amorphous silicon waveguides”, Optics Letters, 36,4, 552-, (2011) [9] S. Selvaraja, et al, “Low-Loss Amorphous Silicon-On-Insulator Technology for Photonic Integrated Circuitry”, Optics Communications, 282(9), p. 1767-1770 (2009). [10] H. Ji, et al, “Fiber Optical Trap Deposition of Carbon Nanotubes on Fiber End-faces in a Modelocked Laser”, CLEO’08, CtuV4, (2008). [11] P. A. Andrekson,et al, “Nonlinear optical fiber based high resolution all-optical waveform sampling,” Laser and photonics reviews, No. 3, 231–248 (2007). Th.11.LeSaleve.1.pdf   3 7/27/2011   4:21:49 PMECOC Technical Digest © 2011 OSA

Optical Waveform Sampling of a 320 Gbit/s Serial Data Signal using a Hydrogenated Amorphous Silicon Waveguide

Optical waveform sampling of a 320 Gbits/s serial data signal using a hydrogenated amorphous silicon waveguide

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