Raman spectrum of graphene and graphene layers.
TL;DR: This work shows that graphene's electronic structure is captured in its Raman spectrum that clearly evolves with the number of layers, and allows unambiguous, high-throughput, nondestructive identification of graphene layers, which is critically lacking in this emerging research area.
Abstract: Graphene is the two-dimensional building block for carbon allotropes of every other dimensionality We show that its electronic structure is captured in its Raman spectrum that clearly evolves with the number of layers The D peak second order changes in shape, width, and position for an increasing number of layers, reflecting the change in the electron bands via a double resonant Raman process The G peak slightly down-shifts This allows unambiguous, high-throughput, nondestructive identification of graphene layers, which is critically lacking in this emerging research area
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TL;DR: The state-of-the-art in optical trapping at the nanoscale is reviewed, with an emphasis on some of the most promising advances, such as controlled manipulation and assembly of individual and multiple nanostructures, force measurement with femtonewton resolution, and biosensors.
Abstract: Optical trapping and manipulation of micrometre-sized particles was first reported in 1970. Since then, it has been successfully implemented in two size ranges: the subnanometre scale, where light-matter mechanical coupling enables cooling of atoms, ions and molecules, and the micrometre scale, where the momentum transfer resulting from light scattering allows manipulation of microscopic objects such as cells. But it has been difficult to apply these techniques to the intermediate - nanoscale - range that includes structures such as quantum dots, nanowires, nanotubes, graphene and two-dimensional crystals, all of crucial importance for nanomaterials-based applications. Recently, however, several new approaches have been developed and demonstrated for trapping plasmonic nanoparticles, semiconductor nanowires and carbon nanostructures. Here we review the state-of-the-art in optical trapping at the nanoscale, with an emphasis on some of the most promising advances, such as controlled manipulation and assembly of individual and multiple nanostructures, force measurement with femtonewton resolution, and biosensors.
855 citations
TL;DR: In this paper, the authors clarified damping pathways for mid-infrared graphene plasmons, including graphene intrinsic optical phonons and edge scattering, and demonstrated the guiding of a 50-nm-wide structure with an electromagnetic mode area of 10−3 μm2 and a propagation length of 200 nm.
Abstract: Researchers clarify damping pathways for mid-infrared graphene plasmons, including graphene intrinsic optical phonons and edge scattering. They also demonstrate the guiding of mid-infrared graphene plasmons in 50-nm-wide structures with an electromagnetic mode area of 10−3 μm2 and a propagation length of 200 nm.
846 citations
TL;DR: Graphene-based photodetectors can be increased by up to 20 times, because of efficient field concentration in the area of a p-n junction, and wavelength and polarization selectivity can be achieved by employing nanostructures of different geometries.
Abstract: From the wide spectrum of potential applications of graphene, ranging from transistors and chemical sensors to nanoelectromechanical devices and composites, the field of photonics and optoelectronics is believed to be one of the most promising. Indeed, graphene's suitability for high-speed photodetection was demonstrated in an optical communication link operating at 10 Gbit s(-1). However, the low responsivity of graphene-based photodetectors compared with traditional III-V-based ones is a potential drawback. Here we show that, by combining graphene with plasmonic nanostructures, the efficiency of graphene-based photodetectors can be increased by up to 20 times, because of efficient field concentration in the area of a p-n junction. Additionally, wavelength and polarization selectivity can be achieved by employing nanostructures of different geometries.
846 citations
Posted Content•
TL;DR: In this article, an anomalous quantum Hall effect was observed in the first two-dimensional carbon material, which is known as Graphene, and it also provides a bridge between condensed matter physics and quantum electrodynamics and opens new perspectives for carbon-based electronics.
Abstract: Carbon is one of the most intriguing elements in the Periodic Table. It forms many allotropes, some being known from ancient times (diamond and graphite) and some discovered ten to twenty years ago (fullerenes, nanotubes). Quite interestingly, the two-dimensional form (graphene) has been obtained only very recently, and immediately attracted great deal of attention. Electrons in graphene, obeying linear dispersion relation, behave like massless relativistic particles, which results in a number of very peculiar electronic properties observed in this first two-dimensional material: from an anomalous quantum Hall effect to the absence of localization. It also provides a bridge between condensed matter physics and quantum electrodynamics and opens new perspectives for carbon-based electronics.
845 citations
TL;DR: Graphene is one of the most promising materials in nanotechnology and from a theoretical point of view, it provides the ultimate two-dimensional model of a catalytic support as mentioned in this paper, and some promising results have already been obtained with few-layer graphene.
842 citations
References
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28 Jul 2005
TL;DR: PfPMP1）与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。
18,940 citations