10Gbit/s bias-free and error-free all-optical NRZ-OOK to RZ-OOK format conversion using a III-V-on-silicon microdisk resonator

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Ultrafast and bias-free all-optical wavelength conversion using III-V-on-silicon technology

Using a 7.5 μm diameter disk fabricated with III-V-on-silicon fabrication technology, we demonstrate bias-free all-optical wavelength conversion for non-return-to-zero on–off keyed pseudorandom bit sequence (PRBS) data at the speed of 10 Gbits/s with an extinction ratio of more than 12 dB. The working principle of such a wavelength converter is based on free-carrier-induced refractive index modulation in a pump–probe configuration. We believe it to be the first bias-free on-chip demonstration of all-optical wavelength conversion using PRBS data. All-optical gating measurements in the pump–probe configuration with the same device have revealed that it is possible to achieve wavelength conversion beyond 20 Gbits/s

Compact integration of optical sources and detectors on SOI for optical interconnects fabricated in a 200 mm CMOS pilot line

As the demand for bandwidth increases, optical interconnects are coming closer and closer to the chip. Optical interconnects on silicon-on-insulator (SOI) are desirable as this allows for integration with CMOS and the mature processing can be used for photonic integrated circuits. A heterogeneous integration process can be used to include III-V active optical components on SOI. For dense integration compact sources and detectors are required, but they typically need different epitaxial structures to be efficient which limits the integration density. We propose to use an epitaxial structure, which contains both the layers for a laser and for a detector, hereby enabling very compact integration of sources and detectors. Microdisk lasers and waveguide detectors using this epi were completely fabricated in a 200 mm CMOS pilot line and the results are discussed here

Optical characterization of a SCISSOR device.

Here, we report on the design, fabrication and characterization of single-channel (SC-) and dual-channel (DC-) side-coupled integrated spaced sequences of optical resonators (SCISSOR) with a finite number (eight) of microring resonators using submicron silicon photonic wires on a silicon-on-insulator (SOI) wafer. We present results on the observation of multiple resonances in the through and the drop port signals of DC-SCISSOR. These result from the coupled resonator induced transparency (CRIT) which appears when the resonator band (RB) and the Bragg band (BB) are nearly coincident. We also observe the formation of high-Q (> 23000) quasi-localized modes in the RB of the drop transmission which appear when the RB and BB are well separated from each other. These multiple resonances and quasi-localized modes are induced by nanometer-scale structural disorders in the dimension of one or more rings. Finally, we demonstrate the tunability of RB (and BB) and localized modes in the DC-SCISSOR by thermo-optical or free-carrier refraction

Mortality rate related to peripheral arterial disease: A retrospective analysis of epidemiological data (years 2008-2019).

BACKGROUND AND AIMS Peripheral arterial disease (PAD) is one of the most prevalent cardiovascular diseases with more than 230 million people being affected worldwide. As highlighted by the recent European Society of Cardiology guidelines, data on the epidemiology of PAD is urgently needed. METHODS AND RESULTS We accessed the vital registration data of the Veneto region (Northern Italy, approximately five millions inhabitants) covering the period 2008-2019. We computed annual age-standardized rates for PAD reported as the underlying cause of death (UCOD) or as one of multiple causes of death (MCOD). Age-adjusted odds ratios (OR) served to study the association between PAD and cardiovascular comorbidities. The age-standardized mortality rate for PAD as MCOD slightly declined from 19.6 to 17.8 in men and from 10.8 to 9.1 deaths per 100,000 population-years in women. The age-standardized PAD-specific mortality rate (UCOD) remained stable: 3.1 to 3.7 per 100,000 person-years in women (Average Annual Percent Change 1.3, 95% CI -0.8; 3.4%) and 4.4 to 4.3 per 100,000 person-years (Average Annual Percent Change -0.2, 95% CI -3.6; 3.4%) in men. PAD contributed to 1.6% of all deaths recorded in the region. Ischemic heart disease, diabetes mellitus and neoplasms were the most prevalent UCOD among PAD patients. PAD was associated with diabetes mellitus (OR 3.79, 95%CI 3.55-4.06) and chronic kidney diseases (OR 2.73, 95%CI 2.51-2.97) in men, and with atrial fibrillation (OR 2.26, 95%CI 2.10-2.44) in women. CONCLUSION PAD remains a substantial cause of death in the general population of this high-income region of Western Europe with marked sex-specific differences

Engineering the optical properties of silicon using sub-wavelength structures

In most integrated optics platforms, including silicon-on-insulator, only minor modifications in refractive index are possible. The geometry of the waveguiding structure is thus the only degree of freedom for the design of devices. The use of sub-wavelength gratings (SWGs), i.e. structures that are small enough to suppress diffraction effects, enables local engineering of both refractive index and dispersion, thereby opening new possibilities for device design. Here we present some of the recent advances in refractive index and dispersion engineering using silicon SWGs, focussing on ultra-broadband and compact multimode interference couplers and directional couplersThis work was supported by the Spanish Ministerio de Ciencia (project TEC2009-10152), the European Mirthe project (FP7-2010-257980), and the Universidad de Málaga - Campus de Excelencia Internacional Andalucìa Tech

A CMOS Compatible Silicon-on-Insulator Polarization Rotator Based on Symmetry Breaking of the Waveguide Cross Section

[EN] A polarization rotator in silicon-on-insulator technology based on breaking the symmetry of the waveguide cross section is reported. The 25-mu m-long device is designed to be integrated with standard grating couplers without the need for extra fabrication steps. Hence, fabrication is carried out by a 2-etch-step complementary metal-oxide-semiconductor compatible process using 193-nm deep ultraviolet lithography. A polarization conversion efficiency of more than -0.85 dB with insertion losses ranging from -1 to -2.5 dB over a wavelength range of 30 nm is demonstrated. © 1989-2012 IEEEThis work was supported by the European Commission under Project HELIOS (pHotonics Electronics functional Integration on CMOS), FP7-224312, TEC2008-06333 SINADEC and PROMETEO-2010-087 R&D Excellency Program (NANOMET).Aamer, M.; Gutiérrez Campo, AM.; Brimont, ACJ.; Vermeulen, D.; Roelkens, G.; Fedeli, J.; Håkansson, OA.... (2012). A CMOS Compatible Silicon-on-Insulator Polarization Rotator Based on Symmetry Breaking of the Waveguide Cross Section. IEEE Photonics Technology Letters. 24(22):2031-2034. https://doi.org/10.1109/LPT.2012.2218593S20312034242