Related papers: Exceptionally strong phonon scattering by B substi…
A recent Bose-Einstein condensation (BEC) model of several cuprate superconductors is based on bosonic Cooper pairs (CPs) moving in 3D with a quadratic energy-momentum (dispersion) relation. The 3D BEC condensate-fraction vs. temperature…
We discover superconductivity in cubic W3Re2C with chiral structure and the superconducting transition temperature Tc is about 6.2 K. Detailed characterizations and analysis indicate that W3Re2C is a bulk type-II BCS superconductor with…
The experimental results hinting at the room temperature and ambient pressure superconductivity and magnetic levitation in LK-99 attracted an unprecedented interest. While attempts of other teams to reproduce the reported observations on…
Simple cubic phosphorus exhibits superconductivity with a maximum $T_c$ of up to 12 K under pressure. The pressure dependence of $T_c$ cannot be consistently explained with a simple electron-phonon mechanism, which has stimulated…
Silicon carbide (SiC) is a wide band gap semiconductor and an attractive candidate for applications in harsh environments such as space, fusion, or future high luminosity colliders. Due to the large band gap, the leakage currents in SiC…
We theoretically and numerically investigate resonant optical properties of composite structures consisting of several subwavelength resonant diffraction gratings separated by homogeneous layers. Using the scattering matrix formalism, we…
Defects in semiconductors acting as optically active spin qubits are intriguing objects of fundamental study and future technological developments. These defect-based color centers are of particular interest for detection and response to…
Temperature dependent inelastic neutron-scattering measurements of the generalized phonon density-of-states for superconducting MgCNi_3, T_c=8 K, give evidence for a soft-mode behavior of low-frequency Ni phonon modes. Results are compared…
The massless Dirac electrons found at topological insulator surfaces are thought to be influenced very little by weak, non-magnetic disorder. However, a resonance effect of strongly perturbing non-magnetic impurities has been theoretically…
We present several results related to the instability of MoC and MoN in the B1 (sodium chloride) structure. These compounds were proposed as potential superconductors with moderately high transition temperatures. We show that the elastic…
Effects of the superconducting pair potential on the impurity scattering processes in metallic carbon nanotubes are studied theoretically. The backward scattering of electrons vanishes in the normal state. In the presence of the…
An increasing number of theoretical calculations on few-layer materials have been reporting a non-zero sound velocity for all three acoustic phonon modes. In contrast with these reports, here we show that the lowest phonon dispersion branch…
Silicon carbide, a semiconducting material, has gained importance in the fields of ceramics, electronics, and renewable energy due to its remarkable hardness and resistance. In this study, we delve into the impact of nuclear quantum motion,…
Using a three-dimensional microscopic lattice model of a strong topological insulator (TI) we study potential impurities and vacancies in surface and subsurface positions. For all impurity locations we find impurity-induced resonance states…
We show that electron correlations control the photophysics of defects in SiC through both renormalization of the quasiparticle bandstructure and exciton effects. We consider the carbon vacancy, which is a well-identified defect with two…
We examine the effect of acoustic phonon scattering on the conductivity of two-dimensional Dirac electrons. The temperature ($T$) dependence of the conductivity ($\sigma$) is calculated using the electron Green's function with damping by…
Very recently impurity scattering effects on quasiparticles in d-wave superconductors have attracted much attention. Especially, the thermodynamic properties in magnetic fields H are of interest. We have measured the low-temperature…
Using the Tc formula given by BCS, together with a shear modulus varying with the numbering of planes, we can demonstrate that Tc oscillates depending on the number of the cuprate planes. The maximum of Tc in these oscillations appears for…
Superconductivity-induced changes of phonon lineshapes in niobium have been re-investigated by high-resolution inelastic neutron scattering. We show that the changes go beyond a simple change in lifetime and frequency when the phonon…
Recent advances in the characterization of hexagonal-diamond silicon (2H-Si) have shown that this material possesses remarkably different structural, electronic, and optical properties as compared to the common cubic-diamond (3C) polytype.…