Band 1, Heft 4

No abstract available.

Electronic phase separation is one of the most exciting findings during the study of strongly correlated electron systems in past decades. Inhomogeneities at the nanoscale have been proven to not only play a key role in the material properties but also challenge the fundamental concepts of condensed matter physics. In rare earth doped manganites, a nanoscale phase with unique structural modulations has attracted particular attention because of its relationship with the renowned behavior of the material, colossal magnetoresistance (CMR). Direct observations of the nanoscale phases are usually difficult but necessary to unravel the controversies and unveil the underlying physics in this case. In this review paper, recent achievements of direct imaging of the nanoscale phase are shown by using advanced transmission electron microscopic techniques correlated with the material property measurements. Based on those results, the relationship between the nanoscale phase and the CMR effect was established, and unexpected magnetic and physical properties of the nanoscale phase were found. Although the microscopic origin of the nanoscale phase is not fully interpreted yet, the findings here shed light on the pathway to a deeper understanding of the mechanism of CMR and other properties in these materials.

Near-field scanning optical microscopy (NSOM) is a powerful method for the optical imaging of surfaces with a resolution down to the nanometer scale. By focusing an external electromagnetic field to the subwavelength aperture or apex of a sharp tip, the diffraction limit is avoided and a near-field spot with a size on the order of the aperture or tip diameter can be created. This point light source is used for scanning a sample surface and recording the signal emitted from the small surface area that interacts with the near field of the probe. In tip-enhanced Raman spectroscopy, such a tip configuration can be used as well to record a full spectrum at each image point, from which chemically specific spectral images of the surface can be extracted. In either case, the contrast and resolution of the images depend critically on the properties of the NSOM probe used in the experiment. In this review, an overview of eligible tip properties and different approaches for tailoring specifically engineered NSOM probes is given from a fabrication point of view.

This review focuses on the optical theory and applications of a single subwavelength aperture in a metal film. We begin with Bethe’s aperture theory for the optical transmission through a subwavelength aperture in a perfect electric conductor film and extend the discussion to apertures in real metals of finite thickness and to apertures with different shapes. Extraordinary optical transmission (EOT) is reviewed, particularly for an aperture in a transverse waveguide screen and for waveguide EOT with applications to aperture near-field probes. We overview applications of single subwavelength nanoapertures to refractive index sensing, single molecule fluorescence detection, Raman spectroscopy and optical trapping of dielectric nanoparticles, including biological matter. Finally, we discuss the potential of combining these many different capabilities to create greater functionality with a single aperture.

Polymeric nanocomposite materials that are highly thermally conductive are important to a variety of applications, with examples ranging from flexible radiators in space to high-performance aircrafts and vehicles and to cutting-edge electronics. Among widely used nanoscale fillers in the development of these materials are carbon nanotubes and graphene sheets. As concluded in previous reviews, the performance of carbon nanotubes for imparting high thermal conductivity into polymeric matrices was generally poor. Here recent results associated with the effort on significant performance improvements are reviewed as an update. By contrast, graphene sheets have emerged as effective nanoscale fillers for polymeric nanocomposites of excellent thermal transport performance, reaching levels that are competitive to those achieved by metals. The significant recent results on thermally conductive polymeric nanocomposites with graphene sheets are highlighted, and their potential applications and issues on their further performance improvements are discussed.

This report summarizes the pioneering educational curricula, world-class technological capabilities, and unmatched economic impact of the College of Nanoscale Science and Engineering (CNSE) of the University at Albany-State University of New York. The combination of advanced 300-mm lithography, 3Di, and fully integrated processing capabilities, combined with a strong academic background in materials characterization and metrology, allows the NanoCollege to offer a unique test bed for advanced device and circuit concepts.

By the Leahy-Smith America Invents Act (AIA), the U.S. patent system is experiencing the most significant reform since the U.S. Patent Act was enacted some 60 years ago. This article focuses on one aspect of the AIA that has perhaps triggered the biggest debate, namely the conversion under the U.S. Patent laws from a “first-to-invent” system to a “first-inventor-to-file” system. The change to the first-inventor-to file system has broad implications to all entities filing patents in the U.S. Under the new first-inventor-to-file system, the emphasis is now on filing patent applications in the U.S. Patent Office even more quickly than before. Thus, a strategy to file early and often (including using provisional applications) will generally better protect against a later inventor winning the race to the U.S. Patent Office.