172 research outputs found
InP/InGaAs photodetector on SOI photonic circuitry
We present an InP-based membrane p-i-n photodetector on a silicon-on-insulator sample containing a Si-wiring photonic circuit that is suitable for use in optical interconnections on Si integrated circuits (ICs). The detector mesa footprint is 50 mu m(2), which is the smallest reported to date for this kind of device, and the junction capacitance is below 10 fF, which allows for high integration density and low dynamic power consumption. The measured detector responsivity and 3-dB bandwidth are 0.45 A/W and 33 GHz, respectively. The device fabrication is compatible with wafer-scale processing steps, guaranteeing compatibility toward future-generation electronic IC processing
Label swapper device for spectral amplitude coded optical packet networks monolithically integrated on InP
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.19.013540. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under lawIn this paper the design, fabrication and experimental characterization of an spectral amplitude coded (SAC) optical label swapper monolithically integrated on Indium Phosphide (InP) is presented. The device has a footprint of 4.8x1.5 mm 2 and is able to perform label swapping operations required in SAC at a speed of 155 Mbps. The device was manufactured in InP using a multiple purpose generic integration scheme. Compared to previous SAC label swapper demonstrations, using discrete component assembly, this label swapper chip operates two order of magnitudes faster. © 2011 Optical Society of America.The activities have been carried out in the framework of the Joint Research Activity (JRA) 'Active-phased Arrayed Devices' (WP 44) of the European Commission FP6 Network of Excellence ePIXnet (European Network of Excellence on Photonic Integrated Components and Circuits), Project Reference: 004525, http://www.epixnet.org/. This work has been partially funded through the Spanish Plan Nacional de I+D+i 2008-2011 project TEC2008-06145/TEC. It has also been partially supported by the Canadian Institute for Photonic Innovations. Devices are presently being fabricated through the InP Photonic Integration Platform JePPIX (coordinator D J Robbins), at the COBRA fab, http://www.jeppix.eu/Muñoz Muñoz, P.; Garcia-Olcina, R.; Habib, C.; Chen, LR.; Leijtens, XJM.; De Vries, T.; Robbins, D.... (2011). Label swapper device for spectral amplitude coded optical packet networks monolithically integrated on InP. Optics Express. 19(14):13540-13550. https://doi.org/10.1364/OE.19.013540S13540135501914Yoo, S. J. B. (2006). Optical Packet and Burst Switching Technologies for the Future Photonic Internet. Journal of Lightwave Technology, 24(12), 4468-4492. doi:10.1109/jlt.2006.886060Blumenthal, D. J., Olsson, B.-E., Rossi, G., Dimmick, T. E., Rau, L., Masanovic, M., ⊠Barton, J. (2000). All-optical label swapping networks and technologies. Journal of Lightwave Technology, 18(12), 2058-2075. doi:10.1109/50.908817Srivatsa, A., d. Waardt, H., Hill, M. T., Khoe, G. D., & Dorren, H. J. S. (2001). All-optical serial header processing based on two-pulse correlation. Electronics Letters, 37(4), 234. doi:10.1049/el:20010178Gordon, R. E., & Chen, L. R. (2006). Demonstration of all-photonic spectral label-switching for optical MPLS networks. IEEE Photonics Technology Letters, 18(4), 586-588. doi:10.1109/lpt.2006.870188Habib, C., Baby, V., Chen, L. R., Delisle-Simard, A., & LaRochelle, S. (2008). All-Optical Swapping of Spectral Amplitude Code Labels Using Nonlinear Media and Semiconductor Fiber Ring Lasers. IEEE Journal of Selected Topics in Quantum Electronics, 14(3), 879-888. doi:10.1109/jstqe.2008.918047Cole, C., Huebner, B., & Johnson, J. (2009). Photonic integration for high-volume, low-cost applications. IEEE Communications Magazine, 47(3), S16-S22. doi:10.1109/mcom.2009.4804385Calabretta, N., Jung, H.-D., Llorente, J. H., Tangdiongga, E., Koonen, T. A. M. J., & Dorren, H. J. S. (2009). All-Optical Label Swapping of Scalable In-Band Address Labels and 160-Gb/s Data Packets. Journal of Lightwave Technology, 27(3), 214-223. doi:10.1109/jlt.2008.2009319Smit, M. K., & Van Dam, C. (1996). PHASAR-based WDM-devices: Principles, design and applications. IEEE Journal of Selected Topics in Quantum Electronics, 2(2), 236-250. doi:10.1109/2944.577370Eisenstein, G. (1989). Semiconductor optical amplifiers. IEEE Circuits and Devices Magazine, 5(4), 25-30. doi:10.1109/101.29899Munoz, P., Pastor, D., & Capmany, J. (2002). Modeling and design of arrayed waveguide gratings. Journal of Lightwave Technology, 20(4), 661-674. doi:10.1109/50.996587Soldano, L. B., & Pennings, E. C. M. (1995). Optical multi-mode interference devices based on self-imaging: principles and applications. Journal of Lightwave Technology, 13(4), 615-627. doi:10.1109/50.372474Zilkie, A. J., Meier, J., Mojahedi, M., Poole, P. J., Barrios, P., Poitras, D., ⊠Aitchison, J. S. (2007). Carrier Dynamics of Quantum-Dot, Quantum-Dash, and Quantum-Well Semiconductor Optical Amplifiers Operating at 1.55 . IEEE Journal of Quantum Electronics, 43(11), 982-991. doi:10.1109/jqe.2007.90447
An introduction to InP-based generic integration technology
Photonic integrated circuits (PICs) are considered as the way to make photonic systems or subsystems cheap and ubiquitous. PICs still are several orders of magnitude more expensive than their microelectronic counterparts, which has restricted their application to a few niche markets. Recently, a novel approach in photonic integration is emerging which will reduce the R&D and prototyping costs and the throughput time of PICs by more than an order of magnitude. It will bring the application of PICs that integrate complex and advanced photonic functionality on a single chip within reach for a large number of small and larger companies and initiate a breakthrough in the application of Photonic ICs. The paper explains the concept of generic photonic integration technology using the technology developed by the COBRA research institute of TU Eindhoven as an example, and it describes the current status and prospects of generic InP-based integration technology
An introduction to InP-based generic integration technology
Photonic integrated circuits (PICs) are considered as the way to make photonic systems or
subsystems cheap and ubiquitous. PICs still are several orders of magnitude more expensive than their microelectronic counterparts, which has restricted their application to a few niche markets.Recently, a novel approach in photonic integration is emerging which will reduce the R&D and prototyping costs and the throughput time of PICs by more than an order of magnitude. It will bring the application of PICs that integrate complex and advanced photonic functionality on a single chip within reach for a large number of small and larger companies and initiate a breakthrough in the application of Photonic ICs. The paper explains the concept of generic photonic integration technology using the technology developed by the COBRA research institute of TU Eindhoven as an example, and it describes the current status and prospects of generic InP-based integration technology.Funding is acknowledged by the EU-projects ePIXnet, EuroPIC and PARADIGM and the Dutch projects NRC Photonics, MEMPHIS, IOP Photonic Devices and STW GTIP. Many others have contributed and the authors would like to thank other PARADIGM and EuroPIC partners for their help in discussions, particularly Michael Robertson (CIP).This is the final published version distributed under a Creative Commons Attribution License. It can also be viewed on the publisher's website at: http://iopscience.iop.org/0268-1242/29/8/08300
Optoelectronic Studies of Methylammonium Lead Iodide Perovskite Solar Cells with Mesoporous TiO2: Separation of Electronic and Chemical Charge Storage, Understanding Two Recombination Lifetimes, and the Evolution of Band Offsets during J-V Hysteresis
Methylammonium lead iodide (MAPI) cells of the design FTO/sTiO2/ mpTiO2/MAPI/Spiro-OMeTAD/Au, where FTO is fluorine-doped tin oxide, sTiO2 indicates solid-TiO2, and mpTiO2 is mesoporous TiO2, are studied using transient photovoltage (TPV), differential capacitance, charge extraction, current interrupt, and chronophotoamperometry. We show that in mpTiO2/MAPI cells there are two kinds of extractable charge stored under operation: a capacitive electronic charge (∼0.2 μC/ cm2) and another, larger charge (40 μC/cm2), possibly related to mobile ions. Transient photovoltage decays are strongly double exponential with two time constants that differ by a factor of ∼5, independent of bias light intensity. The fast decay (∼1 μs at 1 sun) is assigned to the predominant charge recombination pathway in the cell. We examine and reject the possibility that the fast decay is due to ferroelectric relaxation or to the bulk photovoltaic effect. Like many MAPI solar cells, the studied cells show significant J−V hysteresis. Capacitance vs open circuit voltage (Voc) data indicate that the hysteresis involves a change in internal potential gradients, likely a shift in band offset at the TiO2/MAPI interface. The TPV results show that the Voc hysteresis is not due to a change in recombination rate constant. Calculation of recombination flux at Voc suggests that the hysteresis is also not due to an increase in charge separation efficiency and that charge generation is not a function of applied bias. We also show that the J−V hysteresis is not a light driven effect but is caused by exposure to electrical bias, light or dark.</div
Graphite-protected CsPbBr3 perovskite photoanodes functionalised with water oxidation catalyst for oxygen evolution in water
Metal-halide perovskites have been widely investigated in the photovoltaic sector due to their promising optoelectronic properties and inexpensive fabrication techniques based on solution processing. Here we report the development of inorganic CsPbBr3-based photoanodes for direct photoelectrochemical oxygen evolution from aqueous electrolytes. We use a commercial thermal graphite sheet and a mesoporous carbon scaffold to encapsulate CsPbBr3 as an inexpensive and efficient protection strategy. We achieve a record stability of 30âh in aqueous electrolyte under constant simulated solar illumination, with currents above 2âmAâcmâ2 at 1.23âVRHE. We further demonstrate the versatility of our approach by grafting a molecular Ir-based water oxidation catalyst on the electrolyte-facing surface of the sealing graphite sheet, which cathodically shifts the onset potential of the composite photoanode due to accelerated charge transfer. These results suggest an efficient route to develop stable halide perovskite based electrodes for photoelectrochemical solar fuel generation
Filterless narrowband visible photodetectors
Wavelength selective light detection is crucial for many applications such as imaging and machine vision. Narrowband spectral responses are required for colour discrimination and current systems use broadband photodiodes combined with optical filters. This approach increases architectural complexity, and limits of the quality of colour sensing. Here we report filterless, narrowband red, green, and blue photodiodes with tuneable spectral responses. The devices have simple planar junction architectures with the photoactive layer being a solution processed mixture of either an organohalide perovskite or lead halide semiconductor, and a neutral or cationic organic molecule. The organic molecules modify the optical and electrical properties of the photodiode and facilitate narrowing charge collection narrowing of the device's external quantum efficiency. These red, green, and blue photodiodes all possess full-width-at-half-maxima of <100 nm and performance metrics suitable for many imaging applications
Strategy for large???scale monolithic Perovskite/Silicon tandem solar cell: A review of recent progress
For any solar cell technology to reach the final mass-production/commercialization stage, it must meet all technological, economic, and social criteria such as high efficiency, large-area scalability, long-term stability, price competitiveness, and environmental friendliness of constituent materials. Until now, various solar cell technologies have been proposed and investigated, but only crystalline silicon, CdTe, and CIGS technologies have overcome the threshold of mass-production/commercialization. Recently, a perovskite/silicon (PVK/Si) tandem solar cell technology with high efficiency of 29.1% has been reported, which exceeds the theoretical limit of single-junction solar cells as well as the efficiency of stand-alone silicon or perovskite solar cells. The International Technology Roadmap for Photovoltaics (ITRPV) predicts that silicon-based tandem solar cells will account for about 5% market share in 2029 and among various candidates, the combination of silicon and perovskite is the most likely scenario. Here, we classify and review the PVK/Si tandem solar cell technology in terms of homo- and hetero-junction silicon solar cells, the doping type of the bottom silicon cell, and the corresponding so-called normal and inverted structure of the top perovskite cell, along with mechanical and monolithic tandemization schemes. In particular, we review and discuss the recent advances in manufacturing top perovskite cells using solution and vacuum deposition technology for large-area scalability and specific issues of recombination layers and top transparent electrodes for large-area PVK/Si tandem solar cells, which are indispensable for the final commercialization of tandem solar cells
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