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  • 1
    Publication Date: 2008-11-07
    Description: With the realization of faster telecommunication data rates and an expanding interest in ultrafast chemical and physical phenomena, it has become important to develop techniques that enable simple measurements of optical waveforms with subpicosecond resolution. State-of-the-art oscilloscopes with high-speed photodetectors provide single-shot waveform measurement with 30-ps resolution. Although multiple-shot sampling techniques can achieve few-picosecond resolution, single-shot measurements are necessary to analyse events that are rapidly varying in time, asynchronous, or may occur only once. Further improvements in single-shot resolution are challenging, owing to microelectronic bandwidth limitations. To overcome these limitations, researchers have looked towards all-optical techniques because of the large processing bandwidths that photonics allow. This has generated an explosion of interest in the integration of photonics on standard electronics platforms, which has spawned the field of silicon photonics and promises to enable the next generation of computer processing units and advances in high-bandwidth communications. For the success of silicon photonics in these areas, on-chip optical signal-processing for optical performance monitoring will prove critical. Beyond next-generation communications, silicon-compatible ultrafast metrology would be of great utility to many fundamental research fields, as evident from the scientific impact that ultrafast measurement techniques continue to make. Here, using time-to-frequency conversion via the nonlinear process of four-wave mixing on a silicon chip, we demonstrate a waveform measurement technology within a silicon-photonic platform. We measure optical waveforms with 220-fs resolution over lengths greater than 100 ps, which represent the largest record-length-to-resolution ratio (〉450) of any single-shot-capable picosecond waveform measurement technique. Our implementation allows for single-shot measurements and uses only highly developed electronic and optical materials of complementary metal-oxide-semiconductor (CMOS)-compatible silicon-on-insulator technology and single-mode optical fibre. The mature silicon-on-insulator platform and the ability to integrate electronics with these CMOS-compatible photonics offer great promise to extend this technology into commonplace bench-top and chip-scale instruments.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Foster, Mark A -- Salem, Reza -- Geraghty, David F -- Turner-Foster, Amy C -- Lipson, Michal -- Gaeta, Alexander L -- England -- Nature. 2008 Nov 6;456(7218):81-4. doi: 10.1038/nature07430.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18987739" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 2
    Publication Date: 2009-01-06
    Description: The ability to manipulate nanoscopic matter precisely is critical for the development of active nanosystems. Optical tweezers are excellent tools for transporting particles ranging in size from several micrometres to a few hundred nanometres. Manipulation of dielectric objects with much smaller diameters, however, requires stronger optical confinement and higher intensities than can be provided by these diffraction-limited systems. Here we present an approach to optofluidic transport that overcomes these limitations, using sub-wavelength liquid-core slot waveguides. The technique simultaneously makes use of near-field optical forces to confine matter inside the waveguide and scattering/adsorption forces to transport it. The ability of the slot waveguide to condense the accessible electromagnetic energy to scales as small as 60 nm allows us also to overcome the fundamental diffraction problem. We apply the approach here to the trapping and transport of 75-nm dielectric nanoparticles and lambda-DNA molecules. Because trapping occurs along a line, rather than at a point as with traditional point traps, the method provides the ability to handle extended biomolecules directly. We also carry out a detailed numerical analysis that relates the near-field optical forces to release kinetics. We believe that the architecture demonstrated here will help to bridge the gap between optical manipulation and nanofluidics.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yang, Allen H J -- Moore, Sean D -- Schmidt, Bradley S -- Klug, Matthew -- Lipson, Michal -- Erickson, David -- England -- Nature. 2009 Jan 1;457(7225):71-5. doi: 10.1038/nature07593.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19122638" target="_blank"〉PubMed〈/a〉
    Keywords: Bacteriophage lambda/genetics ; DNA, Viral/*analysis ; Electrons ; Kinetics ; Micromanipulation/instrumentation/*methods ; Nanoparticles/*analysis ; *Optical Tweezers ; Optics and Photonics/*instrumentation/*methods
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 3
    Publication Date: 2009-11-17
    Description: The use of optical forces to manipulate small objects is well known. Applications include the manipulation of living cells by optical tweezers and optical cooling in atomic physics. The miniaturization of optical systems (to the micro and nanoscale) has resulted in very compliant systems with masses of the order of nanograms, rendering them susceptible to optical forces. Optical forces have been exploited to demonstrate chaotic quivering of microcavities, optical cooling of mechanical modes, actuation of a tapered-fibre waveguide and excitation of the mechanical modes of silicon nano-beams. Despite recent progress in this field, it is challenging to manipulate the optical response of photonic structures using optical forces; this is because of the large forces that are required to induce appreciable changes in the geometry of the structure. Here we implement a resonant structure whose optical response can be efficiently statically controlled using relatively weak attractive and repulsive optical forces. We demonstrate a static mechanical deformation of up to 20 nanometres in a silicon nitride structure, using three milliwatts of continuous optical power. Because of the sensitivity of the optical response to this deformation, such optically induced static displacement introduces resonance shifts spanning 80 times the intrinsic resonance linewidth.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wiederhecker, Gustavo S -- Chen, Long -- Gondarenko, Alexander -- Lipson, Michal -- England -- Nature. 2009 Dec 3;462(7273):633-6. doi: 10.1038/nature08584. Epub 2009 Nov 15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14853, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19915549" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 4
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 198 (1963), S. 1149-1150 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] ON May 3 the Prime Minister of the Commonwealth of Australia, Sir Robert Menzies, officially opened a new laboratory block at the C.S.I.R.O. Division of Textile Industry, Geelong (Fig. 1). A large gathering was present from many spheres, including parliamentary and civic representatives, as well as ...
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 7 (1963), S. 2053-2066 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Experimental results for the sorption of liquid ethanol by a variety of modified wools are described. Even slight changes in the chemical and physical structure of wool produced large changes in ethanol sorption rate. Blocking of amino groups decreased the sorption rate due to removal of primary sorption sites, but, surprisingly, carboxyl group modification greatly increased the rate. Modification of disulfide crosslinks increased the rate, while in most cases surface modification decreased it, which is contrary to expectation if a surface barrier to diffusion of penetrants is assumed. Theories are advanced for the observed changes in sorption properties and for the small changes found when water if used as sorbate. Saturation sorption values showed only slight changes from that for untreated wool. The largest increases resulted from disulfide bond modification, which is explained as due to lower resistance of the treated wool to swelling forces, allowing greater swelling and sorption.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Publication Date: 1963-06-01
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Springer Nature
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