• Mar 03 2011

    UCT Physics Colloquim: Dr Mecit Yaman, UNAM-National Nanotechnology Research Center, Bilkent University, Turkey

    Dear all,

    on Thursday, Dr Mecit Yaman, UNAM-National Nanotechnology Research Center, Bilkent University, Turkey, will give a presentation

    Drawing nanostructures
    In this talk, I will present fiber making as a nanofabrication technique for nanowire fabrication and for optofluidics channel production.

    1. In nanowire/nanotube fabrication: We have recently developed a new size reduction method by thermal drawing to produce indefinitely long, ordered nanowire and nanotube arrays. Materials used are Sulphur, Selenium and Tellurium based amourphous semiconductors, polyvinylidene fluoride and high temperature polymers. In this way kilometer long, dielectric embedded, ordered nanowire arrays are obtained. Examples of these unusual nanostructures will be shown, their physical properties and possible uses will be discussed.
    2. In optofluidics channel fabrication: Fiber drawing is used to produce a microfluidic fibers with the capability of selective infrared light transmission. The fibers used as a cross responsive sensor array for sensitive (nanomolar) and selective (potentially hundreds of analytes and their mixtures) differentiation of volatile organics. Statistical analysis shows that infrared absorption based transducing with optofluidic fibers can be used as a real time electronic nose. I will also venture into the possible scientific visualization of complex metabolic processes underlying disease onset and pharmacological response from exhaled breath with such an electronic nose.

    The talk will cover a range of topics including the discussion of infrared transmitting chalcogen glass synthesis and their optical characterization with spectroscopic ellipsometry, fabrication of nanostructured, hollow core, wavelength scalable infrared transmitting fibers, infrared absorption spectroscopy, and resonant dielectric nanowires.

    [1] H. Esat Kondakci, Mecit Yaman, Ozlem Koylu, Aykutlu Dana, Mehmet Bayindir, All-chalcogenide glass omnidirectional photonic band gap variable infrared filters, Appl. Phys. Lett., 94, 111110, 2009.
    [2] Mecit Yaman, H. Esat Kondakci, Mehmet Bayindir, Large and dynamical tuning of a chalcogenide Fabry-Perot cavity mode by temperature modulation, Optics Express, 18, 3168, 2010.
    [3] Adem Yildirim, Mert Vural, Mecit Yaman, Mehmet Bayindir, Bioinspired Optoelectronic Nose with Nanostructured Wavelength-Scalable Hollow-Core Infrared Fibers, DOI: 10.1002/adma.201004052, 2010.
    when: Thu, 3 March 2011, 12:00 to 13:00
    where: Duncan Elliott Seminar Room, RW James Building

    All welcome!