Metamaterials with Hyperbolic Dispersion
M. A. Noginov
Center for Materials Research, Norfolk State University, Norfolk, VA 23504
Friday Sept 28, 2012 at 11:00 am
in Osborne A204
Metamaterials – engineered composite materials with sub-wavelength inclusions – havereceived widespread attention due to their ability to manipulate light in unconventional ways, as exemplified by negative index of refraction, optical cloaking, and limitless focusing. Metamaterials with hyperbolic dispersion, also known as indefinite media, is an important class of metamaterials, in which dielectric permittivities in orthogonal directions have opposite signs. This property enables propagation of waves with nominally infinitely large wavevectors and infinite density of photonic states. Metamaterials with hyperbolic dispersion support and facilitate scores of unparalleled phenomena (including but not limited to sub-diffraction imaging, control of spontaneous emission, and perfect absorption), which will be discussed in the presentation.
Magnetodynamics and magnetostatics in nano-scale structures and spintronic materials.
Michael Pechan, Department of Physics, Miami University
Osborne Center for Science and Engineering A204
Friday Sept 21, 2012 1:00 pm
Following a brief introduction, I will discuss our recent and ongoing investigations in nanoscale physics and spintronics. The main probe utilized in this talk is ferromagnetic resonance. First I will discuss magnetostatic and magnetodynamic effects in exchange coupled permalloy nano-dots in collaboration with Hitachi Global Storage. Next I will present anisotropy and damping results in single crystal films of Fe3O4 on MgO with and without a silver overlayer (to probe spin-pumping effects) from room temperature through the Verwey transition. This project is done in collaboration with Casey Miller at U of South Florida. Finally, I will describe some new and exciting spectra arising from hard/soft, core/shell nanoparticles done in collaboration with Josep Nogues from Unviversitat Autònama de Barcelona, Spain.