Due to the effects of surface electromigration, waves can propagate over the free surface of a current-carrying metallic or semiconducting film of thickness h(0). In this paper, waves of finite amplitude, and slow modulations of these waves, are studied. Periodic wave trains of finite amplitude are found, as well as their dispersion relation. If the film material is isotropic, a wave train with...

Metallic and semiconducting carbon nanotubes generally coexist in as-grown materials. We present a gas-phase plasma hydrocarbonation reaction to selectively etch and gasify metallic nanotubes, retaining the semiconducting nanotubes in near-pristine form. With this process, 100% of purely semiconducting nanotubes were obtained and connected in parallel for high-current transistors. The diameter-...

We studied the femtosecond dynamics of photoexcitations in films containing semiconducting and metallic single-walled carbon nanotubes (SWNTs), using various pump-probe wavelengths and intensities. We found that confined excitons and charge carriers with subpicosecond dynamics dominate the ultrafast response in semiconducting and metallic SWNTs, respectively. Surprisingly, we also found from th...

In this Communication, we show that nanometer scale control of semiconducting polymer chain conformation is possible using host/guest chemistry in highly ordered and macroscopically oriented thin films of mesoporous silica. This control leads to a thin film composite material that is optically transparent, densely filled with polymer, and has highly polarized optical properties. Calculations of...

A fast, simple, scalable technique is described for the controlled, solution-based, electrochemical synthesis of patterned metallic and semiconducting nanowires from reusable, nonsacrificial, ultrananocrystalline diamond (UNCD) templates. This enables the repeated fabrication of arrays of complex patterns of nanowires, potentially made of any electrochemically depositable material. Unlike all o...

We investigate the lower limit of nanowire diameters stably produced by the process of thermal fiber drawing and fiber tapering. A centimeter-scale macroscopic cylindrical preform containing the nanowire material in the core encased in a polymer scaffold cladding is thermally drawn in the viscous state to a fiber. By cascading several iterations of the process, continuous reduction of the diame...

The semiconducting properties of molecular material prototypes for graphene nanoribbons are rationalized by quantum-chemical calculations. The present contribution focuses on the hole transport properties of circum(oligo)acenes and compares the intrinsic efficiency of these materials for charge transport in the hopping regime with respect to the (oligo)acenes parent compounds. The results at th...

1. INTRODUCTION Single-walled carbon nanotubes (SWNTs) are a promising material for next generation field-effect transistors (FETs) [1]. It is one of the most important requirements to obtain purely semiconducting SWNT arrays. Recently, Jin et al. [2] have reported a method to selectively remove metallic SWNTs over the whole length by using thermocapillary flows of organic thin films. Here, we ...

5.1 Anodic Aluminum Oxide (AAO) Templated Nanowires Due to their small sizes and potential for controllable features, nanowires/tubes represent an attractive option for increasing the surface area of ceria-based anodes. Templated approaches are currently the most flexible routes to fabricating nanowires/tubes, as only a suitable filling method needs be developed for a particular material compos...