A visible negative-index metamaterial was fabricated by adopting a template-assisted and self-assembled electrochemical deposition method. Originating from the inherent characteristic of bottom-up fabrication, it has been demonstrated by the effective medium theory that the metamaterial resonance could realize a negative index at visible wavelengths if the degree of asymmetry is kept in a moder...

Van der Waals interactions have a fundamental role in biology, physics and chemistry, in particular in the self-assembly and the ensuing function of nanostructured materials. Here we utilize an efficient microscopic method to demonstrate that van der Waals interactions in nanomaterials act at distances greater than typically assumed, and can be characterized by different scaling laws depending ...

The ability to control dynamically the flow and placement of nanoscale particles and biomolecules in a biocompatible, aqueous environment will have profound impact in advancing the fields of nanoplasmonics, nanophotonics, and medicine. Here, an approach based on electrokinetic forces is demonstrated that enables dynamically controlled placement of nanoparticles into a predefined pattern. The te...

Nanoelectronic devices offer substantial potential for interrogating biological systems, although nearly all work has focused on planar device designs. We have overcome this limitation through synthetic integration of a nanoscale field-effect transistor (nanoFET) device at the tip of an acute-angle kinked silicon nanowire, where nanoscale connections are made by the arms of the kinked nanostruc...

We show that a periodic metal-metal multilayer nanostructure can serve as an efficient source of hard x-ray transition radiation. Our research effort is aimed at developing an x-ray source for medical applications, which is based on using low-energy relativistic electrons. The approach toward choosing radiator-spacer couples for the generation of hard x-ray resonant transition radiation by few-...

Structural colors are generated by scattering of light by variations in tissue nanostructure. They are widespread among animals and have been studied most extensively in butterflies and moths (Lepidoptera), which exhibit the widest diversity of photonic nanostructures, resultant colors, and visual effects of any extant organism. The evolution of structural coloration in lepidopterans, however, ...

High-resolution electron microscopy imaging and electron and X-ray diffraction techniques have been used to characterize the structure of low and high flux Au-20%Pd layers in Au-20%Pd/MoS2 multilayer solid lubricant thin films. Images clearly reveal different morphologies for the metal layers in the two flux regimes, which can be correlated to the variation in fracture resistance reported by an...

Micrometer long multilayer carbon nanoribbons with high oxygen content and nitrogen doping were obtained from the nitric acid treatment of Black Pearls 2000. The (NRs) exhibited yellow light emission under UV excitation. oxidation other grades black yielded irregular small graphene oxide fragments or quantum dots instead. Remarkably, familiar straightforward materials reemerges as a powerful to...

A complex three-dimensional (3D) feather-like AlN nanostructure was synthesized by a direct reaction of high-purity Al granules with nitrogen using an arc discharge method. By adjusting the discharge time, a coral-like nanostructure, which evolved from the feather-like nanostructure, has also been observed. The novel 3D feather-like AlN nanostructure has a hierarchical dendritic structure, whic...