375 research outputs found

    Multi-level optical signal generation using a segmented-electrode InP IQ-MZM with integrated CMOS binary drivers

    Get PDF
    We present a segmented-electrode InP IQ-MZM, capable of multi-level optical signal generation (5-bit per I/Q arm) by employing direct digital drive from integrated, low-power (1W) CMOS binary drivers. Programmable, multi-level operation is demonstrated experimentally on one MZM of the device

    Quaternary TDM-PAM as upgrade path of access PON beyond 10Gb/s

    Get PDF
    A 20 Gb/s quaternary TDM-PAM passive optical network with chirped and non-linear optical transmitters is experimentally demonstrated. The migration from legacy TDM-PONs and the implications of using available 10 Gb/s components are analyzed. We show that a loss budget of 27.3 dB is compatible together with a packet power ratio of 10 dB between loud and soft optical network units. (c) 2012 Optical Society of Americ

    PAM-4 and duobinary direct modulation of a hybrid InP/SOI DFB laser for 40 Gb/s transmission over 2 km single mode fiber

    Get PDF
    We demonstrate 40 Gb/s PAM-4 and Duobinary direct modulation of a heterogeneously integrated InP on SOI DFB laser. Transmission measurement was performed using a 2 km NZ-DSF with a PRBS 2(15) and 1.5 V-pp swing voltage

    Towards Brain Imaging using THz Technology

    Get PDF
    Abstract- We demonstrate recent advances towards the development of a novel 2-D THz imaging system for brain imaging applications both at macroscopic and at biomolecule level. A frequency synthesized THz source based on Difference Frequency Generation between optical wavelengths is presented, utilizing supercontinuum generation in a highly-nonlinear optical fiber with subsequent spectral carving by means of a fiber FabryPerot filter. Experimental results confirm the successful generation of THz radiation in the range of 0.2-2 THz, verifying the enhanced frequency tunability properties of the proposed system. Finally, the roadmap towards capturing functional brain information by exploiting THz imaging technologies is discussed, outlining the unique advantages offered by THz frequencies and their complementarity with existing brain imaging techniques

    Linear and nonlinear optical properties of some organoxenon derivatives

    Get PDF
    We employ a series of state-of-the-art computational techniques to study the effect of inserting one or more Xe atoms in HC2H and HC4H, on the linear and nonlinear optical (L&NLO) properties of the resulting compounds. It has been found that the inserted Xe has a great effect on the L&NLO properties of the organoxenon derivatives. We analyze the bonding in HXeC2H, and the change of the electronic structure, which is induced by inserting Xe, in order to rationalize the observed extraordinary L&NLO properties. The derivatives, which are of interest in this work, have been synthesized in a Xe matrix. Thus the effect of the local field (LF), due to the Xe environment, on the properties of HXeC2H, has also been computed. It has been found that the LF effect on some properties is significant. The calculations have been performed by employing a hierarchy of basis sets and the techniques MP2 and CCSD(T) for taking into account correlation. For the interpretation of the results we have employed the complete active space valence bond and CASSCF/CASPT2 [email protected]

    Figure 1: Experimental setup 40 Gb/s NRZ Wavelength Conversion with Enhanced 2R Regeneration Characteristics using a Differentially-biased SOA-MZI switch

    Get PDF
    Abstract We present error-free 40 Gb/s NRZ signal wavelength conversion with a differential biasing scheme in a SOA -Mach Zehnder Interferometer. Experimental performance analysis shows 1.7 dB negative power penalty and enhanced 2R regenerative characteristics

    O-band QKD link over a multiple ONT loaded carrier-grade GPON for FTTH applications

    Full text link
    We have successfully integrated an O-band commercial Quantum-Key-Distribution (QKD) system over a lit GPON testbed that replicates a carrier-grade Fiber-to-the-Home (FTTH) optical access network with multiple ONTs to emulate real-life FTTH operational deployments.Comment: 3 page

    Completion of neuronal remodeling prompts myelination along developing motor axon branches

    Get PDF
    Neuronal remodeling and myelination are two fundamental processes during neurodevelopment. How they influence each other remains largely unknown, even though their coordinated execution is critical for circuit function and often disrupted in neuropsychiatric disorders. It is unclear whether myelination stabilizes axon branches during remodeling or whether ongoing remodeling delays myelination. By modulating synaptic transmission, cytoskeletal dynamics, and axonal transport in mouse motor axons, we show that local axon remodeling delays myelination onset and node formation. Conversely, glial differentiation does not determine the outcome of axon remodeling. Delayed myelination is not due to a limited supply of structural components of the axon–glial unit but rather is triggered by increased transport of signaling factors that initiate myelination, such as neuregulin. Further, transport of promyelinating signals is regulated via local cytoskeletal maturation related to activity-dependent competition. Our study reveals an axon branch–specific fine-tuning mechanism that locally coordinates axon remodeling and myelination
    corecore