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Localized Wannier functions provide an efficient and intuitive means by which to compute dielectric properties from first principles. They are most commonly constructed in a post-processing step, following total-energy minimization. Nonorthogonal generaliz ...
The spin-wave band structure of a two-dimensional square array of NiFe circular antidots (hole diameter 120 nm, periodicity 800 nm) is investigated. Brillouin light scattering experiments and band structure calculations, carried out by means of the dynamic ...
The dynamics of acoustic vibrations in terahertz quantum cascade laser structures (THz-QCLs) is studied by means of femtosecond pump-probe spectroscopy. The phonon modes are characterized by the folding of the acoustic dispersion into an effective reduced ...
We propose a novel helical crystal lattice model for chiral and achiral carbon nanotubes (CNTs) where the unit cell and the helical crystal vector are defined in a unique and systematic manner for arbitrary CNTs. The small unit cell of this helical crystal ...
Recent theoretical calculations and experimental results suggest that the strongly correlated material SmB6 may be a realization of a topological Kondo insulator. We have performed an angle-resolved photoemission spectroscopy study on SmB6 in order to eluc ...
In this work, we design, fabricate and experimentally characterize a surface structured lens within an ultra thin polymer layer deposited on a Bloch Surface Waves (BSWs) suspended dielectric platform. The near-field (SNOM) measurements demonstrate that the ...
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 ...
In this work, we use a novel platform concept based on Bloch Surface Waves (BSWs) and manipulate the BSWs propagation with two-dimensional (2D) dielectric patterns deposited on it. The concept opens a way to realize 2D integrated all-optics systems includi ...
The spin-wave band structure of a two-dimensional bicomponent magnonic crystal, consisting of Co nanodisks partially embedded in a Permalloy thin film, is experimentally investigated along a high-symmetry direction by Brillouin light scattering. The eigenf ...
Based on density functional theory, the electronic and optical properties of hybrid organic/perovskite crystals are thoroughly investigated. We consider the monocrystalline 4F-PEPI as material model and demonstrate that the optical process is governed by t ...