Few-layer GaSe is one of the latest additions to the family of two-dimensional semiconducting crystals whose properties under strain are still relatively unexplored. Here, we study rippled nanosheets that exhibit a periodic compressive and tensile strain of up to 5%. The strain profile modifies the local optoelectronic properties of the alternating compressive and tensile regions, which translates into a remarkable shift of the optical absorption band-edge of up to 1.
View Article and Find Full Text PDFGraphene edges present localized electronic states strongly depending on their shape, size and border configuration. Chiral- or zigzag-ended graphene nanostructures develop spatially and spectrally localized edge states around the Fermi level; however, atomic scale investigations of such graphene terminations and their related electronic states are very challenging and many of their properties remain unexplored. Here we present a combined experimental and theoretical study on graphene stripes showing strong metallic edge states at room temperature.
View Article and Find Full Text PDFThe Indian gharial (Gavialis gangeticus) is not found in saltwater, but the geographical distribution of fossil relatives suggests a derivation from ancestors that lived in, or were at least able to withstand, saline conditions. Here, we describe a new Oligocene gharial, Aktiogavialis puertoricensis, from deltaic-coastal deposits of northern Puerto Rico. It is related to a clade of Neogene gharials otherwise restricted to South America.
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