Community Speakers: Jasmine Sears and Israel Vaughn

    Friday, March 13, 2015 - 12:00pm - 1:00pm
    Meinel 408

    Ph.D. student Israel Vaughn will present "Bandwidth in Modulated Mueller Polarimeters." Ph.D. student Jasmine Sears will present "Elemental Composition Analysis of Self-Assembled Indium Islands."


    "Bandwidth in Modulated Mueller Polarimeters": Imaging polarimeters have been largely used for remote sensing tasks, and most imaging polarimeters are division-of-time or division-of-space Stokes polarimeters. Imaging Mueller matrix polarimeters, which can take data quickly enough to be useful for remote sensing tasks, have just begun to be constructed. Vaughn's group has constructed a full Mueller matrix polarimeter utilizing a hybrid modulation approach (modulated in both time and space) based on a micropolarizer-array camera and rotating retarders. They introduce a channel structure derived from the spatiotemporal modulation and optimize over control parameters to minimize channel crosstalk. They present an instrument utilizing this hybrid approach and illustrate issues with systematic errors induced from nonideal polarization elements.

    "Elemental Composition Analysis of Self-Assembled Indium Islands": Metallic nanostructures can act as optical antennas, interacting with near-visible light instead of long radio waves. E-beam lithography has been used to fabricate arrays of silver nano-antennas, but this process isn’t scalable and can be finicky. What if we could coax these nano-antennas into assembling themselves, instead? Using transmission electron microscopy and energy dispersive spectroscopy, Sears will examine the purity and structure of self-assembled indium islands to evaluate their potential as near-infrared antennas.