Scaling Up the Production of Electrodeposited Nanowires: A Roadmap towards Applications

The use of metallic nanowires is mostly reduced to scientific areas where a small quantity of nanostructures are needed. In order to broaden the applicability of these nanomaterials, it is necessary to establish novel synthesis protocols that provide a larger amount of nanowires than the conventional laboratory fabrication processes at a more competitive cost. In this work, we propose several modifications to the conventional electrochemical synthesis of nanowires in order to increase the production with considerably reduced production time and cost. To that end, we use a soft anodization procedure of recycled aluminum at room temperature to produce the alumina templates, followed by galvanostatic growth of CoFe nanowires. We studied their morphology, composition and magnetic configuration, and found that their properties are very similar to those obtained by conventional methods.

Nanowires Integrated to Optical Waveguides

Chip-scale integrated optical devices are one of the most developed research subjects in last years. These devices serve as a bridge to overcome size mismatch between diffraction-limited bulk optics and nanoscale photonic devices. They have been employed to develop many on-chip applications, such as integrated light sources, polarizers, optical filters, and even biosensing devices. Among these integrated systems can be found the so-called hybrid photonic-plasmonic devices, structures that integrate plasmonic metamaterials on top of optical waveguides, leading to outstanding physical phenomena. In this contribution, we present a comprehensive study of the design of hybrid photonic-plasmonic systems consisting of periodic arrays of metallic nanowires integrated on top of dielectric waveguides. Based on numerical simulations, we explain the physics of these structures and analyze light coupling between plasmonic resonances in the nanowires and the photonic modes of the waveguides below them. With this chapter we pretend to attract the interest of research community in the development of integrated hybrid photonic-plasmonic devices, especially light interaction between guided photonic modes and plasmonic resonances in metallic nanowires.

Non-contact Local Conductivity Measurement of Metallic Nanowires Based on Semi-near-field Reflection of Microwave Atomic Force Microscopy

In this study, a non-contact and quantitative evaluation method was developed to measure the conductivity of metallic nanowires with a nanometer-scale spatial resolution. A coaxial probe was experimentally fabricated; using this probe, microwave images of the Al, Ag, and Cu nanowires and their topography images were simultaneously obtained via microwave atomic force microscopy (M-AFM) in the non-contact mode. A semi-near-field reflection model was established to describe the spatial distribution of a microwave between the tip of the probe and the sample. The local conductivities of metallic nanowires on the nanometer-scale can be quantitatively evaluated in a single scan, using a metal strip substrate to calibrate the reflection signal.