A5044802462- Physics of Superconductivity and Magnetism
- Electronic and Structural Properties of Oxides
- Semiconductor materials and devices
- High-pressure geophysics and materials
- Quantum and electron transport phenomena
- Quantum, superfluid, helium dynamics
- Quantum many-body systems
- Semiconductor materials and interfaces
- Magnetic and transport properties of perovskites and related materials
- Solidification and crystal growth phenomena
- European Criminal Justice and Data Protection
- Advanced Condensed Matter Physics
- Advanced Electron Microscopy Techniques and Applications
- Advancements in Semiconductor Devices and Circuit Design
- nanoparticles nucleation surface interactions
- Cybercrime and Law Enforcement Studies
- Quantum Chromodynamics and Particle Interactions
- Magnetic properties of thin films
- Heat and Mass Transfer in Porous Media
- Nonlinear Photonic Systems
- Cellular and Composite Structures
- Magnetic Properties and Applications
- Spectroscopy and Quantum Chemical Studies
- Surface and Thin Film Phenomena
- Nonlinear Dynamics and Pattern Formation
TU Wien
2023-2025
Institute of Physics
2020-2024
We examine the standard model of many-body localization (MBL), i.e., disordered chain interacting spinless fermions, by representing it as network in (MB) basis noninteracting localized Anderson states. By studying eigenstates full Hamiltonian, for strong disorders we find that dynamics is confined up to very long times disconnected MB clusters Fock space. keeping only resonant contributions and simplifying quantum problem rate equations (REs) states, analogy with percolation problems, MBL...
Conflicting theoretical scenarios for infinite-layer nickelate superconductors have been hotly debated, particularly regarding whether only a single Ni-<a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mn>3</a:mn><a:msub><a:mi>d</a:mi><a:mrow><a:msup><a:mi>x</a:mi><a:mn>2</a:mn></a:msup><a:mo>−</a:mo><a:msup><a:mi>y</a:mi><a:mn>2</a:mn></a:msup></a:mrow></a:msub></a:mrow></a:math> band is relevant at low energies besides electron pockets or multiorbital physics including...
Numerous angle resolved photoemission spectroscopy (ARPES) studies of a wide class low-density metallic systems, ranging from doped transition metal oxides to quasi two-dimensional interfaces between insulators, exhibit phonon sidebands below the quasi-particle peak as unique hallmark polaronic correlations. Here, we single out properties ARPES spectra that can provide robust estimate effective range (screening length) electron-phonon interaction, regardless limited experimental resolution,...
The generalized Drude formula is used to study conductivity properties of the two-dimensional weakly doped Holstein model with a free-electron-like dispersion. relaxation processes associated scattering conduction electrons by optical phonons are described in terms frequency- and temperature-dependent memory function. imaginary real parts function analyzed detail regime when characteristic energy scales problem, i.e., electron Fermi phonon energy, comparable size. Results obtained at zero...
The scattering of electrons on impurities with internal degrees freedom is bound to produce the signatures scatterer's own dynamics and results in nontrivial electronic transport properties. Previous studies polaronic low-dimensional structures, like molecular junctions one-dimensional nanowire models, have shown that perturbative treatments cannot account for a complex energy dependence cross section such systems. Here we derive exact solution shaping bulk (3D) In model short-ranged...
A systematic analysis of phonon-plasmon coupled excitations in three-dimensional (3D) polar systems is provided through the prism both raw and integrated electron energy loss spectroscopy (EELS) phonon spectra whole relevant parametric space, spanned by adiabaticity parameter electron-phonon interaction (EPI) strength. We show that EPI strength plays a prominent role distributing spectral weights among excitations, providing an experimentally convenient way to estimate it from spectra. By...
We investigate the dynamical effects of electron-phonon coupling (EPC) on superconducting properties two-dimensional (2D) systems, calculating Eliashberg function in terms dynamically renormalized phonons. By studying different approximations for phonon self-energy, we identify important role charge fluctuations shaping superconductivity properties, not only through renormalization frequencies and damping rates but also structural changes spectral function. With treated consistently, argue...
Correlated electron systems often show strong bosonic fluctuations, e.g., of antiferromagnetic nature, around a large wave vector such as $\mathbf{q}=(\ensuremath{\pi},\ensuremath{\pi}...)$. These fluctuations can give rise to vertex corrections the optical conductivity through (transversal) particle-hole channel, coined $\ensuremath{\pi}$-ton contributions. Previous numerical results differed qualitatively on how alter conductivity. Here we clarify that lead displaced Drude peak, by...
Conflicting theoretical scenarios for infinite-layer nickelate superconductors have been hotly debated, particularly regarding whether {only} a single Ni-3$d_{x^2-y^2}$ band is relevant at low energies besides electron pockets or multi-orbital physics including Ni-3$d_{z^2}$ instead essential. The first scenario has emerged from density-functional theory plus dynamical mean-field (DFT+DMFT) calculations. Comparing the previous DFT+DMFT spectra to recent angular-resolved photoemission...
Vertex corrections from the transversal particle-hole channel, so-called $\pi$-tons, are generic in models for strongly correlated electron systems and can lead to a displaced Drude peak (DDP). Here, we derive analytical expression these how they affect optical conductivity as function of correlation length $\xi$, fermion lifetime $\tau$, temperature $T$, coupling strength spin or charge fluctuations $g$. In particular, $T\rightarrow T_c$, critical antiferromagnetic ordering, dc vertex...
We investigate and compare different approaches for handling the dynamical effects of electron-phonon coupling (EPC) on superconducting properties two-dimensional (2D) systems in presence plasmons. By calculating Eliashberg function terms dynamically renormalized phonons, we discuss approximations frequently used literature them to a fully treatment screening effects. emphasize importance consistent calculations charge fluctuations that shape properties, not only through renormalization...
Foaming metals modulates their physical properties, enabling attractive applications where lightweight, low thermal conductivity or acoustic isolation are desirable. Adjusting the size of bubbles in foams is particularly relevant for targeted applications. Here we provide a method with detailed theoretical understanding how to tune aluminium melts in-situ via pressure. Our description full agreement high-rate three-dimensional X-Ray radioscopy bubble formation. We complement our study...