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The thermal conductivity of disordered silicon-germanium alloys is computed from density-functional perturbation theory and with relaxation times that include both harmonic and anharmonic scattering terms. We show that this approach yields an excellent agr ...
Dichlorocarbene is added to the sidewalls of single-walled carbon nanotubes (SWNTs) with diameters ranging from 1.2 to 2.2 nm. Small diameter SWNTs are found to react much more easily than large diameter SWNTs. Upon functionalization, the conductance could ...
We introduce an improvement to the Hubbard U augmented density functional approach known as DFT+U that incorporates variations in the value of self-consistently calculated, linear-response U with changes in geometry. This approach overcomes the one major s ...
We address the issue of the low electrical conductivity observed in carbon nanotube networks using first-principles calculations of the structure, stability, and ballistic transport of different nanotube junctions. We first study covalent linkers, using th ...
We use first-principles methods based on density functional perturbation theory to characterize the lifetimes of the acoustic phonon modes and their consequences on the thermal transport properties of graphene. We show that using a standard perturbative ap ...
The electronic ground state of a periodic system is usually described in terms of extended Bloch orbitals, but an alternative representation in terms of localized "Wannier functions" was introduced by Gregory Wannier in 1937. The connection between the Blo ...
Room-temperature ionic liquids (RTILs) have attracted much attention in the scientific community in the past decade due their novel and highly customizable properties. Nonetheless, their high viscosities pose serious limitations to the use of RTILs in prac ...
Pure metallic single-walled carbon nanotubes (m-SWCNTs) are very desirable for many electrode and interconnecting applications. However, the lack of reliable processing techniques to sort m-SWCNTs from the as-synthesized SWCNT samples is an obstacle to the ...
Ever since the novel quantum Hall effect in bilayer graphene was discovered, and explained by a Berry phase of 2 pi [K. S. Novoselov et al., Nat. Phys. 2, 177 (2006)], it has been widely accepted that the low-energy electronic wave function in this system ...
The thermal conductivity of ideal short-period superlattices is computed using harmonic and anharmonic force constants derived from density-functional perturbation theory and by solving the Boltzmann transport equation in the single-mode relaxation time ap ...
