Archive for August, 2011

Prof. Dr. Jeremy Witzens

  Prof. Dr. Jeremy Witzens Email: jwitzens “at” iph.rwth-aachen.de Phone: +49 241 80 20021 Dr. Witzens received his M.Sc. (“Diplôme d’Ingénieur”) from the Ecole Polytechnique (France) in 2000 and his PhD from the California Institute of Technology in 2005. From

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Design of CMOS integrated germanium photodiodes

Abstract: A CMOS processing compatible germanium on silicon integrated waveguide photodiode. Positioning contacts in predicted low optical field regions, establishing side trenches in the silicon layer along the length of the photodiode reduces optical losses. Novel taper dimensions are selected

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Optical Telecommunications 2: Systems (Summer Semesters)

Syllabus of the lecture – Optical Telecommunications 2: Systems 1. Transceiver Architectures Block-diagrams of transmitters and receivers, direct laser modulation and external modulation, offset compensation, clock data recovery, transimpedance amplifiers, limiting amplifiers. 2. Fundamentals of Signal Analysis Eye diagrams, signal

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Optical Telecommunications 1: Devices (Winter Semesters)

Syllabus of the lecture – Optical Telecommunications 1: Devices 1.       Introduction to Guided Wave Optics and Optical Communications Systems Glass fiber technologies, Planar Lightwave Circuit (PLC) technologies, optical modes, waveguide dispersion, introduction to single-mode and multimode optics,

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Integrated Photonics Seminar (Summer Semester 2011)

Description: The goal of this seminar is for the students to cover the most important topics in Integrated Photonics in view of understanding a complete optical communications link. During the seminar, you will be coached by the scientific team of

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Polarization splitting grating couplers

Abstract: A polarization splitting grating coupler (PSGC) connects an optical signal from an optical element, such as a fiber, to an optoelectronic integrated circuit. The PSGC separates a received optical signal into two orthogonal polarizations and directs the two polarizations

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Wafer-level testing of optical and optoelectronic chips

Abstract: This application describes, among others, wafer designs, testing systems and techniques for wafer-level optical testing by coupling probe light from top of the wafer. L. C. Gunn, R. Malendevich, T. Pinguet, M. Rattier, M. Sussman, J. Witzens, Wafer-Level Testing

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10Gbit/s transceiver on silicon

Abstract: We discuss our approach to monolithic integration of Germanium photodectors with CMOS electronics for high speed optical transceivers. Integration into the CMOS process and optimization of optical coupling into the devices is described, followed by a discussion on how

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Theoretical Study of Optical Rectification at Radio Frequencies in a Slot Waveguide

Abstract: We present a theoretical study of optical rectification (OR) at radio frequencies (RF). OR is a process by which a second-order nonlinear optical material can directly convert an optical field into an RF electric field. The combination of high-index

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Demonstration of a low VπL modulator with GHz bandwidth based on electro-optic 
polymer-clad silicon slot waveguides

Abstract: We demonstrate a near-infrared electro-optic modulator with a bandwidth of 3 GHz and a VπL figure of merit of 0.8 V-cm using a push-pull configuration. This is the highest operating speed achieved in a silicon-polymer hybrid system to date

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