Seminar
■ 제 목 : Fabrication, linear and nonlinear spectroscopy of optical nano-antennas and hybrid antenna-systems
■ 연 사 : Monika Fleischer (Institute for applied physics and center for light-matter-interaction, Eberhard Karls University Tübingen)
■ 일 시 : 2017년 9월 12일(화) 오후 3시
■ 장 소 :응용공학동 (W1-1) 2425호
■ Host : 정연식 교수
■ Abstract : Plasmonic
nanostructures that act as optical nano-antennas for visible light offer
interesting opportunities for locally concentrating and enhancing the electric field
of an incident light wave, or of spectrally tuning the antenna characteristics
via the size, shape and material. By combining the antenna structures with a
second component in hybrid configurations, such as quantum dots, fluorescent
molecules, or organic thin-films, the antennas can be employed to modify the
absorption and emission characteristics of these objects in the coupled system.
Key challenges in this context are the optimization of the antenna properties
in view of the envisaged application, as well as achieving selective coupling
of the nano-emitters to the high near-field regions of individual antennas.
In this
presentation the Eberhard Karls University Tübingen in Germany and its Core
Facility, the Center for Light-Matter-Interaction, Sensors and Analytics (LISA+)
will shortly be introduced. The top-down nanofabrication of optical nano-antennas
by various nano-lithographic techniques, combined with etch-mask transfer, will
be demonstrated. Their linear and nonlinear optical properties are
investigated. Conical nanoantennas offer narrow, high near-field intensity
hotspots near their tip apexes. Procedures for selectively coupling few or
single nano-emitters to these tips will be shown. Applications of different
hybrid antenna configurations for absorption or emission enhancement, lifetime
reduction, and biosensing through plasmon resonance shifts in a microfluidic
environment will be illustrated.