291 research outputs found
40 Gbit/s silicon-organic hybrid (SOH) phase modulator
A 40 Gbit/s electro-optic modulator is demonstrated. The modulator is based on a slotted silicon waveguide filled with an organic material. The silicon organic hybrid (SOH) approach allows combining highly nonlinear electro-optic organic materials with CMOS-compatible silicon photonics technology
Characterizing and modeling backscattering in silicon microring resonators
This paper was published in OPTICS EXPRESS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OE.19.024980. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under lawWe present an experimental technique to characterize back-scattering in silicon microring resonators, together with a simple analytical model that reproduces the experimental results. The model can extract all the key parameters of an add-drop-type resonator, which are the loss, both coupling coefficients and backscattering. We show that the backscattering effect strongly affects the resonance shape, and that consecutive resonances of the same ring can have very different backscattering parameters. © 2011 Optical Society of America.The authors acknowledge financial support from the Spanish Ministry of Science and Innovation through contract SINADEC (TEC2008-06333). Joaquin Matres is supported by the Formacion de Personal Investigador grant program of the Universidad Politecnica de Valencia.Ballesteros GarcĂa, G.; Matres Abril, J.; MartĂ Sendra, J.; Oton Nieto, CJ. (2011). Characterizing and modeling backscattering in silicon microring resonators. Optics Express. 19(25):24980-24985. https://doi.org/10.1364/OE.19.024980S24980249851925De Vos, K., Bartolozzi, I., Schacht, E., Bienstman, P., & Baets, R. (2007). Silicon-on-Insulator microring resonator for sensitive and label-free biosensing. Optics Express, 15(12), 7610. doi:10.1364/oe.15.007610Almeida, V. R., Barrios, C. A., Panepucci, R. R., & Lipson, M. (2004). All-optical control of light on a silicon chip. Nature, 431(7012), 1081-1084. doi:10.1038/nature02921Dumon, P., Bogaerts, W., Wiaux, V., Wouters, J., Beckx, S., Van Campenhout, J., … Baets, R. (2004). Low-Loss SOI Photonic Wires and Ring Resonators Fabricated With Deep UV Lithography. IEEE Photonics Technology Letters, 16(5), 1328-1330. doi:10.1109/lpt.2004.826025Morichetti, F., Canciamilla, A., Martinelli, M., Samarelli, A., De La Rue, R. M., Sorel, M., & Melloni, A. (2010). Coherent backscattering in optical microring resonators. Applied Physics Letters, 96(8), 081112. doi:10.1063/1.3330894Little, B. E., Laine, J.-P., & Chu, S. T. (1997). Surface-roughness-induced contradirectional coupling in ring and disk resonators. Optics Letters, 22(1), 4. doi:10.1364/ol.22.000004Kippenberg, T. J., Spillane, S. M., & Vahala, K. J. (2002). Modal coupling in traveling-wave resonators. Optics Letters, 27(19), 1669. doi:10.1364/ol.27.001669Zhang, Z., Dainese, M., Wosinski, L., & Qiu, M. (2008). Resonance-splitting and enhanced notch depth in SOI ring resonators with mutual mode coupling. Optics Express, 16(7), 4621. doi:10.1364/oe.16.004621Morichetti, F., Canciamilla, A., Ferrari, C., Torregiani, M., Melloni, A., & Martinelli, M. (2010). Roughness Induced Backscattering in Optical Silicon Waveguides. Physical Review Letters, 104(3). doi:10.1103/physrevlett.104.033902Little, B. E., Chu, S. T., Haus, H. A., Foresi, J., & Laine, J.-P. (1997). Microring resonator channel dropping filters. Journal of Lightwave Technology, 15(6), 998-1005. doi:10.1109/50.588673Morichetti, F., Canciamilla, A., & Melloni, A. (2010). Statistics of backscattering in optical waveguides. Optics Letters, 35(11), 1777. doi:10.1364/ol.35.001777McKinnon, W. R., Xu, D. X., Storey, C., Post, E., Densmore, A., Delâge, A., … Janz, S. (2009). Extracting coupling and loss coefficients from a ring resonator. Optics Express, 17(21), 18971. doi:10.1364/oe.17.01897
Transcriptional regulation of SPROUTY 2 by MYB influences myeloid cell proliferation and stem cell properties by enhancing responsiveness to IL-3.
Myeloproliferative neoplasms (MPN), which overproduce blood cells in the bone marrow, have recently been linked with a genetically determined decrease in expression of the MYB transcription factor. Here, we use a mouse MYB knockdown model with an MPN-like phenotype to show how lower levels of MYB lead to stem cell characteristics in myeloid progenitors. The altered progenitor properties feature elevated cytokine responsiveness, especially to IL-3, which results from increased receptor expression and increased MAPK activity leading to enhanced phosphorylation of a key regulator of protein synthesis, ribosomal protein S6. MYB acts on MAPK signaling by directly regulating transcription of the gene encoding the negative modulator SPRY2. This mechanistic insight points to pathways that might be targeted therapeutically in MPN.Leukemia accepted article preview online, 17 October 2016. doi:10.1038/leu.2016.289
100 Gbit/s electro-optic modulator and 56 Gbits/s wavelength converter for DQPSK data in silicon-organic hybrid (SOH) technology
CMOS-compatible silicon photonics combined with covers of chi (2) or chi (3)-nonlinear organic material allows electro-optic modulators and all-optical wavelength converters for data rates of 100 Gbit/s and beyond. The devices are not impaired by free carriers
Silicon high-speed electro-optic modulator
A 40 Gbit/s electro-optic modulator is demonstrated. The modulator is based on a slotted silicon waveguide filled with a nonlinear organic material. A modulation voltage-length product of V π L = 0.21 Vcm can be achieved
Lasing in silicon-organic hybrid waveguides
Silicon photonics enables large-scale photonic–electronic integration by leveraging highly developed fabrication processes from the microelectronics industry. However, while a rich portfolio of devices has already been demonstrated on the silicon platform, on-chip light sources still remain a key challenge since the indirect bandgap of the material inhibits efficient photon emission and thus impedes lasing. Here we demonstrate a class of infrared lasers that can be fabricated on the silicon-on-insulator (SOI) integration platform. The lasers are based on the silicon–organic hybrid (SOH) integration concept and combine nanophotonic SOI waveguides with dye-doped organic cladding materials that provide optical gain. We demonstrate pulsed room-temperature lasing with on-chip peak output powers of up to 1.1 W at a wavelength of 1,310 nm. The SOH approach enables efficient mass-production of silicon photonic light sources emitting in the near infrared and offers the possibility of tuning the emission wavelength over a wide range by proper choice of dye materials and resonator geometry
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