Enhanced resistance of single-layer graphene to ion bombardment

We report that single-layer graphene on a SiO_2/Si substrate withstands ion bombardment up to ~7 times longer than expected when exposed to focused Ga^+ ion beam. The exposure is performed in a dual beam scanning electron microscope/focused ion beam system at 30 kV accelerating voltage and 41 pA current. Ga^+ ion flux is determined by sputtering a known volume of hydrogenated amorphous carbon film deposited via plasma-enhanced chemical vapor deposition

Nanotextured Surfaces and Related Methods, Systems, and Uses

A method of controlling wetting characteristics is described. Such method includes forming and configuring nanostructures on a surface where controlling of the wetting characteristics is desired. Surfaces and methods of fabricating such surfaces are also described

CAIRS Newsletter 2010

https://aquila.usm.edu/cairs_newsletters/1000/thumbnail.jp

Alien Registration- Greer, F Ientha (Durham, Androscoggin County)

https://digitalmaine.com/alien_docs/30109/thumbnail.jp

Chiral molecular films as electron polarizers and polarization modulators

Recent experiments on electron scattering through molecular films have shown that chiral molecules can be efficient sources of polarized electrons even in the absence of heavy nuclei as source of a strong spin-orbit interaction. We show that self-assembled monolayers (SAMs) of chiral molecules are strong electron polarizers due to the high density effect of the monolayers and explicitly compute the scattering amplitude off a helical molecular model of carbon atoms. Longitudinal polarization is shown to be the signature of chiral scattering. For elastic scattering, we find that at least double scattering events must take place for longitudinal polarization to arise. We predict energy windows for strong polarization, determined by the energy dependences of spin-orbit strength and multiple scattering probability. An incoherent mechanism for polarization amplification is proposed, that increases the polarization linearly with the number of helix turns, consistent with recent experiments on DNA SAMs.Comment: 5 Pages, 4 figure

Designing core-shell 3D photonic crystal lattices for negative refraction

We use a plane wave expansion method to define parameters for the fabrication of 3-dimensional (3D) core-shell photonic crystals (PhCs) with lattice geometries that are capable of all-angle negative refraction (AANR) in the midinfrared centered around 8.0 μm. We discuss the dependence of the AANR frequency range on the volume fraction of solid within the lattice and on the ratio of the low index core material to the high index shell material. Following the constraints set by simulations, we fabricate two types of nanolattice PhCs: (1) polymer core-germanium shell and (2) amorphous carbon core-germanium shell to enable experimental observation of 3D negative refraction and related dispersion phenomena at infrared and eventually optical frequencies