Showing 41 - 50 of 187
We propose a lattice model for Dirac fermions which allows us to break the degeneracy of the node structure. In the presence of a random gap we analyze the scaling behavior of the localization length as a function of the system width within a numerical transfer-matrix approach. Depending on the...
Persistent link: https://www.econbiz.de/10010843659
Propagation in perturbed one-dimensional phononic or photonic crystals, with both compositional and positional disorder, is considered. The coherent potential approximation is used to obtain the band structure and the Floquet normal form of the periodic-on-average perturbed crystal, which is...
Persistent link: https://www.econbiz.de/10010843667
Persistent link: https://www.econbiz.de/10010843672
A number of experimental small-angle scattering (SAS) data are characterized by a succession of power-law decays with arbitrarily decreasing values of scattering exponents. To describe such data, here we develop a new theoretical model based on 3D fat fractals (sets with fractal structure, but...
Persistent link: https://www.econbiz.de/10010843674
In this work, we have considered the pressure induced NaCl (B1) to CsCl (B2) phase transition of yttrium chalcogenides (YX; X=S, Se, Te). An extended interaction potential (EIP) model has been developed (including the zero point energy effect in three body interaction potential model). Phase...
Persistent link: https://www.econbiz.de/10010843683
We discuss the application of the two-band spin-dopon representation of the t-J model to address the issue of the Fermi surface reconstruction observed in the cuprates. We show that the electron no double occupancy (NDO) constraint plays a key role in this formulation. In particular, the...
Persistent link: https://www.econbiz.de/10010843689
Persistent link: https://www.econbiz.de/10010843694
The thermally driven spin transport through mesoscopic ferromagnetic semimetal-normal metal junctions is investigated. A pure spin current can be enforced by the spin-polarised semimetal band structure and the spin current increases with increasing either the temperature bias or the equilibrium...
Persistent link: https://www.econbiz.de/10010843701
By coating a three-dimensional topological insulator (TI) with a ferromagnetic film supporting an in-plane magnetic vortex, one breaks the time-reversal symmetry (TRS) without generating a mass gap. It rather yields electronic states bound to the vortex center which have different probabilities...
Persistent link: https://www.econbiz.de/10010843708
The critical thickness for ferroelectricity and magnetoelectric effects have been investigated for the multiferroic tunnel junction with symmetric and asymmetric metallic electrodes based on density functional theory. The ferroelectric polarization of a barrier is still retained down to 2 unit...
Persistent link: https://www.econbiz.de/10010843712