Related papers: Thickness and strain effects on the thermoelectric…
Materials with ring-shaped electronic bands are promising thermoelectric candidates, since their unusual dispersion shape is predicted to give large power factors. While previous calculations of these materials have relied on the assumption…
We study the transport properties, in particular, the thermoelectric figure of merit ZT of armchair graphene nanoribbons, AGNR-N (for N=4-12, with widths ranging from 3.7 to 13.6~\AA) through strain engineering, where N is the number of…
Bismuth selenide (Bi2Se3) is a prototypical three-dimensional topological insulator whose Dirac surface states have been extensively studied theoretically and experimentally. Surprisingly little, however, is known about the energetics and…
The surface structure of the prototypical topological insulator Bi2Se3 is determined by low-energy electron diffraction and surface X-ray diffraction at room temperature. Both approaches show that the crystal is terminated by an intact…
Stacking polymorphism is a common characteristic of van der Waals layered materials and can substantially modify their physical properties. Here, based on first-principles calculations combined with electron and phonon transport theories,…
The passivation of thin Bi(1 1 1) films with hydrogen and oxide capping layers is investigated from first principles. Considering termination-related changes of the crystal structure, we show how the bands and density of states are…
Layered transition metal dichalcogenides (TMDs) are ideal systems for exploring the effects of dimensionality on correlated electronic phases such as charge density wave (CDW) order and superconductivity. In bulk NbSe2 a CDW sets in at TCDW…
Using first principles density functional theory calculations, we show a semimetal to semiconducting electronic phase transition for bulk TiS 2 by applying uniform biaxial tensile strain. This electronic phase transition is triggered by…
Single layer molybdenum disulfide (SLMoS2), a semiconductor possesses intrinsic bandgap and high electron mobility, has attracted great attention due to its unique electronic, optical, mechanical and thermal properties. Although thermal…
Graphene-based vertical heterostructures, particularly stacks incorporated with other layered materials, are promising for nanoelectronics. The stacking of two model Dirac materials, graphene and topological insulator, can considerably…
The electronic structures of TixZrx/2CoPbxTex, TixZrx/2Hfx/2CoPbxTex (x = 0.5), and the parent compound TiCoSb were investigated using the full potential linearized augmented plane wave method. The thermoelectric transport properties of…
We present first principles study of thermoelectric transport properties of sandwiched heterostructure of Graphene (G)/hexagonal Boron Nitride (BN)/G, based on Boltzmann transport theory for band electrons using the bandstructure calculated…
Double cation chalcohalide have recently been emerged as the interesting candidates for sustainable energy conversion applications, owing to their intrinsic chemical tunability, suitable band gap, and low thermal conductivity. With this…
The exploration of superconductivity in low-dimensional materials has attracted intensive attention for decades. Based on first-principles electronic structure calculations, we have systematically investigated the electronic and…
We theoretically study the thermoelectric transport S in a double-layer bilayer graphene (BLG-GaAs-BLG) system on dielectric substrates (h-BN, Al2O3, HfO2). Electrons interact with GaAs acoustic phonons via both the deformation potential…
We predict the existence of new two dimensional silicon carbide nanostructure employing ab initio density-functional theory calculations. These structures are composed of tetragonal and hexagonal rings with C-C and Si-C bonds arranged in a…
A thin, narrow-bandgap semiconductor Bi$_2$O$_2$Te nanosheet is obtained via mechanical exfoliation and a Hall-bar device is fabricated from it on a heavily doped Si/SiO$_2$ substrate and studied at low temperatures. Gate transfer…
Two-dimensional layered materials have attracted tremendous attentions due to their extraordinary physical and chemical properties. Using first-principles calculations and Boltzmann transport theory, we give an accurate prediction of the…
Carrier and phonon dynamics in Bi2Se3 crystals are studied by a spatially resolved ultrafast pump-probe technique. Pronounced oscillations in differential reflection are observed with two distinct frequencies, and are attributed to coherent…
The thermoelectric properties of n type nanoscale three dimensional (3D) Si phononic crystals (PnCs) with spherical pores are studied. Density functional theory and Boltzmann transport equation under the relaxation time approximation are…