Accepted papers to appear in an upcoming issue
OSA now posts prepublication articles as soon as they are accepted and cleared for production. See the FAQ for additional information.
Single-drive high speed lumped modulators toward 10 fJ/bit energy consumption
Xinbai Li, Fenghe Yang, Fang Zhong, Qingzhong Deng, Jurgen Michel, and Zhiping Zhou
Doc ID: 283879 Received 04 Jan 2017; Accepted 20 Feb 2017; Posted 23 Feb 2017 View: PDF
Abstract: Reduction of modulator energy consumption to 10 fJ/bit is essential for the sustainable development of communication systems. Lumped modulators might be a viable solution if instructed by complete theory system. Here we present complete analytical electro-optic response theory, energy consumption analysis and eye diagrams on absolute scales for lumped modulators. Consequently, the speed limitation is understood and alleviated by single-drive configuration, and comprehensive knowledge into the energy dependence on structural parameters significantly reduces energy consumption. The results show silicon modulation energy as low as 80.8 and 21.5 fJ/bit can be achieved at 28 Gbps under 50 𝛀 and 10 𝛀 impedance driver, respectively. Such figures are 1~2 orders of magnitude lower than traveling wave modulators and previous lumped silicon modulators. 50 Gbps modulation is also shown to be possible. The analytical models can be extended to lumped modulators on other material platforms and offers a promising path to the currently challenging modulation energy reduction.
Electrical nonlinearity in silicon modulators based on reversed PN junctions
Tao Chu and Sheng Yu
Doc ID: 278678 Received 13 Oct 2016; Accepted 13 Feb 2017; Posted 13 Feb 2017 View: PDF
Abstract: The electrical nonlinearity of silicon modulators based on reversed PN junctions was found to severely limit the linearity of the modulators, which was unexpectedly neglected in previous studies. Considering the electrical nonlinearity in simulation, a 32.2-dB degradation in CDR3 (suppression ratio between the fundamental signal and intermodulation distortion) of the modulator was observed at a modulation speed of 12 GHz. The spurious free dynamic range simultaneously degraded by 17.4 dB. It was also found that the linearity of the silicon modulator could be improved by reducing the series resistance of the PN junction. The linearity frequency dependency due to the electrical nonlinearity was also investigated.
Towards 10 Gb/s OFDM-based Visible Light Communicationusing a GaN Violet micro-LED
Mohamed sufyan Islim, Ricardo Ferreira, Xiangyu He, enyuan Xie, Stefan Videv, Shaun Viola, Nikos Bamiedakis, Anthony Kelly, Richard Penty, Ian White, Erdan Gu, Martin D. Dawson, Harald Haas, and Scott Watson
Doc ID: 280671 Received 28 Nov 2016; Accepted 09 Feb 2017; Posted 10 Feb 2017 View: PDF
Abstract: Visible light communication (VLC) is a promising solution to the increasing demands for wireless connectivity.Micro-sized Gallium Nitride (GaN) light emitting diodes (mirco-LEDs) are strong candidates for VLC dueto their high bandwidths. Segmented violet mirco-LEDs are reported in this work with electrical-to-opticalbandwidths up to 655 MHz. An orthogonal frequency division multiplexing (OFDM) based VLC system withadaptive bit and energy loading is demonstrated and a data transmission rate of 11.95 Gb/s is achieved witha violet mirco-LED, when the nonlinear distortion of the mirco-LED is the dominant noise source of the VLCsystem. A record 7.91 Gb/s data transmission rate is reported below the forward error correction thresholdusing a single pixel of the segmented array when all the noise sources of the VLC system are present.
Liquid modified photonic crystal fiber for simultaneous temperature and strain measurement
Changrui Liao, Chupao Lin, Ying Wang, Yijian Huang, Zhiyong Bai, Maoxiang Hou, Zhengyong Li, and Yiping Wang
Doc ID: 282595 Received 09 Dec 2016; Accepted 04 Feb 2017; Posted 13 Feb 2017 View: PDF
Abstract: A liquid modified photonic crystal fiber integrated with an embedded directional coupler and a multi-mode interferometer is fabricated by infiltrating three adjacent air holes of the innermost layer with standard 1.48 refractive index liquids. The refractive index of the filled liquid is higher than that of background silica, which can not only support the transmitting rod modes, but also the modes of “liquid modified core” propagating between the PCF core and the liquid rods. Hence, the light propagated in the liquid modified core can be efficiently coupled into the satellite waveguides under the phase-matching conditions, resulting in dramatic decreasing of the resonant wavelength intensity. Furthermore, there is a multi-mode interference produced by modified core modes and rod modes. Such an compact (~0.91cm) device integrated with an embedded coupler and an interferometer is demonstrated for high sensitivity simultaneous temperature (~14.72 nm / °C ) and strain (~13.01 pm/με) measurement.
InAlGaN superluminescent diodes fabricated on patterned substrates – an alternative semiconductor broadband emitter
Anna Kafar, Szymon Stanczyk, Marcin Sarzynski, Szymon Grzanka, Jakub Goss, Irina Makarowa, Anna Nowakowska-Siwinska, Tadek Suski, and Piotr Perlin
Doc ID: 280364 Received 10 Nov 2016; Accepted 02 Feb 2017; Posted 03 Feb 2017 View: PDF
Abstract: We have demonstrated InGaN, violet light emitting superluminescent diodes with large spectral width suitable for application in optical coherence spectroscopy. This was achieved by using the concept of nonlinear indium content profile along the superluminescent diode waveguide. A specially designed 3D shape of the substrate surface lead to a step-like indium content profile, with the indium concentration in the InGaN/GaN quantum wells ranging approximately between 6% and 10%. Thanks to this approach, in processed devices, we were able to increase the width of the spectrum from 2.6 nm (reference diode) to 15.5 nm.
Compact, submilliwatt, 2 × 2 silicon thermo-optic switch based on photonic crystal nanobeam cavities
huanying zhou, Ciyuan Qiu, Jiang Xinhong, Yu He, yong zhang, Yikai Su, and Richard Soref
Doc ID: 280900 Received 17 Nov 2016; Accepted 26 Jan 2017; Posted 27 Jan 2017 View: PDF
Abstract: We propose and experimentally demonstrate a 2 × 2 thermo-optic (TO) cross-bar switch implemented by dual photonic crystal nanobeam (PCN) cavities within a silicon-on-insulator (SOI) platform. By thermally tuning the refractive index of silicon, the resonance wavelength of the PCN cavities can be red-shifted. With the help of the ultra-small mode volumes of the PCN cavities, only ~0.16-mW power is needed to change the switching state. With a spectral passband of 0.09 nm at the 1583.75-nm operation wavelength, the insertion loss (IL) and crosstalk (CT) performances were measured as IL(bar) = –0.2 dB, CT(bar) = –15 dB, IL(cross) = –1.5 dB and CT(cross) = –15 dB. Furthermore, the thermal tuning efficiency of the fabricated device is as high as 1. nm/mW.
Gap induced mode evolution under the asymmetric structure inplasmonic resonator system
Chuan Wang, Yong-Pan Gao, Tie-Jun Wang, and Cong Cao
Doc ID: 278412 Received 25 Oct 2016; Accepted 23 Jan 2017; Posted 24 Jan 2017 View: PDF
Abstract: The control of resonance features in microcavities is importance for the applications in nanophotonics. Here based on the asymmetric whispering-gallery modes(WGM) in plasmonic resonator, we theoretically studied themode evolution in asymmetric WGM plasmonic system. Exploiting the gap or nano-scatter in the plasmonic ring cavity, the symmetry of the system will be broken and the standing wave in the cavity will be tunable. Based on this asymmetric structure, the output coupling rate between the two cavity modes can also be tuned. Moreover, the proposed method could further been applied for sensing and detecting the position of defects in WGM system.
Experimental observation of Fano-like resonance in a whispering-gallery-mode microresonator in aqueous environment
Mingyong Ye, Yan-Lei Shang, and Lin Xiu-Min
Doc ID: 283182 Received 20 Dec 2016; Accepted 20 Jan 2017; Posted 24 Jan 2017 View: PDF
Abstract: We report transmission spectra of a sausage-like microresonator (SLM) in aqueous environment, where a fiber taper is used as a light coupler. The transmission spectra show an interesting dependence on the coupling position between the SLM and the fiber taper. When the SLM is moved along the fiber taper, the line shape can evolve periodically among symmetric dips, asymmetric Fano-like resonance line shapes and symmetric peaks. A coupled-mode theory with feedback is developed to explain the observation. The observation of Fano-like resonance in aqueous environment holds great potential in biochemical sensing.
High Sensitivity D-shaped Hole Fiber Temperature Sensor based on Surface Plasmon Resonance with Liquid Filling
Li Pei, Sijun Weng, jianshuai wang, Tigang NIng, and Jing Li
Doc ID: 278394 Received 10 Oct 2016; Accepted 03 Jan 2017; Posted 06 Jan 2017 View: PDF
Abstract: A high sensitivity D-shaped hole fiber temperature sensor based on surface plasmon resonance (SPR) is designed and investigated by full-vector finite element method. Within the D-shaped hole fiber, the hollow D-section is coated with gold film and then injected in a high thermo-optic coefficient liquid to realize a high temperature sensitivity for the fiber SPR temperature sensor. The numerical simulation results show that the peaking loss of the D-shaped hole fiber SPR temperature sensor is huge influenced by the distance between the D-shaped hole and fiber core and the thickness of gold film, but the temperature sensitivity is insensitive to the above parameters though. When the thermo-optic coefficient is -2.8×10-4/⁰C, the thickness of gold film is 47 nm and the distance between the D-shaped hole and fiber core is 5 μm, the temperature sensitivity of D-shaped hole fiber SPR sensor can reach to -3.635 nm/⁰C.