Related papers: Screening in YBCO at large wave vectors
Density functional theory methods are applied to investigate the properties of the new superconductor $\beta$-YbAlB$_4$ and its polymorph $\alpha$-YbAlB$_4$. We utilize the generalized gradient approximation + Hubbard U (GGA+U) approach…
With Terahertz and Infrared spectroscopy we studied the in-plane response of an underdoped YBa2Cu3O6.6 single crystal with Tc=58(1) K in high magnetic fields up to B=30 Tesla applied along the c-axis. Our goal was to investigate the…
Optical properties of symmetry-forbidden pi-pi transitions in benzene are calculated with the time-dependent density functional theory (TDDFT), using an adiabatic LDA functional. Quantities calculated are the envelopes of the Franck-Condon…
Thomson scattering spectra measure the response of plasma particles to incident radiation. In warm dense matter, which is opaque to visible light, x-ray Thomson scattering (XRTS) enables a detailed probe of the electron distribution and has…
We describe a new method for imaging ultrafast dynamics in condensed matter using inelastic x-ray scattering (IXS). We use the concepts of causality and irreversibility to construct a general solution to the inverse scattering problem (or…
X-ray absorption spectroscopy yields direct access to the electronic and geometric structure of hybrid inorganic-organic interfaces formed upon adsorption of complex molecules at metal surfaces. The unambiguous interpretation of…
Under the Franck-Condon approximation, we systematically validated the performance of density functional theory (DFT) and the effects of anharmonicity in simulating C/N/O K-edge vibrationally-resolved X-ray spectra of common diatomic…
We study possible optically excited bound states in monolayer MoS2: excitons and trions. For this purpose we formulate and apply a generalized time-dependent density-matrix functional approach for bound states of multiple excitations. The…
Excitation energies of light-emitting organic conjugated polymers have been investigated with time-dependent density functional theory (TDDFT) within the adiabatic approximation for the dynamical exchange-correlation potential. Our…
An explicit expression for the quadratic density-response function of a many-electron system is obtained in the framework of the time-dependent density-functional theory, in terms of the linear and quadratic density-response functions of…
Time-dependent density functional theory (TDDFT) has been applied to the calculation of absorption spectra for two-dimensional atomic layer materials. We reveal that the character of the first bright exciton state of bi-layer hexagonal…
The electromagnetic response to microwaves in the mixed state of YBa2Cu3Oy(YBCO) was measured in order to investigate the electronic state inside and outside the vortex core. The magnetic-field dependence of the complex surface impedance at…
Delafossite PdCrO$_2$ is an intriguing material which displays nearly-free electron and Mott insulating behaviour in different layers. Both angle-resolved photoemission spectroscopy (ARPES) and Compton scattering measurements have…
We present a detailed Cu K-edge resonant inelastic X-ray scattering (RIXS) study of the Mott insulator La2CuO4 in the 1-7 eV energy transfer range. As initially found for the high-temperature superconductor HgBa2CuO4+d, the spectra exhibit…
The theoretical calculation of the interaction of electromagnetic radiation with matter remains a challenging problem for contemporary $ab$ $initio$ electronic structure methods, in particular for x-ray spectroscopies. This is not only due…
We propose a computationally efficient approach to the nonadiabatic time-dependent density functional theory (TDDFT) which is based on a representation of the frequency-dependent exchange correlation kernel as a response of a set of damped…
High temperature superconductors, especially YBa$_2$Cu$_3$O$_{7-\delta}$ (YBCO), are considered a key enabling technology towards a clean energy future. Hole doping in YBCO is a prerequisite for the emergence of its unchallenged…
We illustrate the scope of Time Dependent Density Functional Theory (TDDFT) for strongly correlated (lattice) models out of equilibrium. Using the exact many body time evolution, we reverse engineer the exact exchange correlation (xc)…
The effect of high-energy electron irradiation on the temperature dependences of the resistivity $\rho(T)$, fluctuation conductivity (FLC), and pseudogap (PG) $\Delta^{*}(T)$ of YBa$_2$Cu$_3$O$_7$--$\delta$ (YBCO) single crystals without…
Results of resonant inelastic X-ray scattering (RIXS) measurements at Fe L-edges and electronic structure calculations of LiFeAs and NaFeAs are presented. Both experiment and theory show that in the vicinity of the Fermi energy, the density…