Ultrathin topological insulator nanostructures, in which coupling between top and bottom surface states takes place, are of great intellectual and practical importance. Due to the weak van der Waals interaction between adjacent quintuple layers (QLs), the layered bismuth selenide (Bi(2)Se(3)), a single Dirac-cone topological insulator with a large bulk gap, can be exfoliated down to a few QLs. ...

Few layer bismuth nanofilms with (111) orientation have shown striking electronic properties, especially as building blocks of novel two-dimensional heterostructures. In this paper we present state-of-the-art first principles calculations, based on both density functional theory and maximally localized Wannier functions, that encompass electronic and structural properties of free-standing Bi(11...

Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. Here, we report the observation of weak anti-localization and quantum oscillations originated from surface states in Bi₂Se₂Te crystals. Angle-resolved photoemission spectrosco...

The discovery of carbon nanotubes has initiated an exciting, intellectually challenging, and rapidly expanding research field for one-dimensional (1D) nanostructures.1 Over the past several years, considerable efforts have been placed on the synthesis of nanotubes or nanowires. A particularly significant breakthrough in MX2 (M: Mo or W, X: S or Se) nanotube synthesis was made by Tenne and co-wo...

Bismuth sulphide (Bi2S3), an n-type semiconductor that critically demonstrates the Seebeck effect with coefficients of about 300 μVK−1. However, its poor electrical conductivity makes it unsuitable for thermoelectric applications. In this study, we present a facile preparation method fabricating Bi-sprayed Bi2S3 particles alters their properties. Samples were created differing Bi concentrations...

Polycrystalline thin films of Bi 2 Te 3 , a well-known topological insulator (TI), grown by RF sputtering shows metallic-like transport for wide range temperatures, T = 50 K to 225 K. For > K, the sample activated transport.. The behavior at low temperatures can be understood within model overlapping surface states TI nanocrystallites in film, suggesting that polycrystalline nature may also ...

this review reports recent advances in metallic nanostructures based electrochemical sensors. interesting aspects of nps include size and shape-dependent interatomic bond distances, melting points, chemical reactivity, and optical and electronic properties. the small size of metallic nanostructures has allowed nanoscale electrochemical processes to be probed. electrochemical characteristics can...

Bi$_2$Se$_3$, a layered three dimensional (3D) material, exhibits topological insulating properties due to presence of surface states and band gap 0.3 eV in the bulk. We study effect hydrostatic pressure $P$ doping with rare earth elements on aspect this material bulk from first principles perspective. Our shows that under moderate P$>$7.9 GPa, electronic show transition an Weyl semi-metal stat...