A5064605898- Quantum and electron transport phenomena
- Magnetic and transport properties of perovskites and related materials
- Semiconductor Quantum Structures and Devices
- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- Quantum Dots Synthesis And Properties
- Rare-earth and actinide compounds
- GaN-based semiconductor devices and materials
- Semiconductor Lasers and Optical Devices
Masaryk University
2019-2024
TU Wien
2023
Český Metrologický Institut
2019-2021
Many mechanisms for unconventional superconductivity have been proposed, but actually proving which one is in charge challenging. Quite astonishingly, dynamical vertex approximation predict the superconducting phase diagram of novel nickelate superconductors, with microscopic origin being antiferromagnetic spin fluctuations. The authors compare fluctuations behind these calculations to experiment. again good agreement gives an overall coherent and complete picture, thus a high level...
We present a detailed investigation of different excitonic states weakly confined in single GaAs/AlGaAs quantum dots obtained by the Al droplet-etching method. For our analysis we make use temperature-, polarization- and magnetic field-dependent $\mu$-photoluminescence measurements, which allow us to identify excited dot system. Besides that, comprehensive g-factors diamagnetic coefficients charged neutral Voigt Faraday configuration. Supported theoretical calculations Configuration...
Detailed theoretical study of the magneto-optical properties weakly confining GaAs/AlGaAs quantum dots is provided. We focus on diamagnetic coefficient and $g$-factor neutral charged excitonic states, respectively, their evolution with various dot sizes for magnetic fields applied along $[001]$ direction. For calculations we utilize combination ${\bf k}\cdot{\bf p}$ configuration interaction methods. decompose theory into four levels precision,~i.e., (i) single-particle electron hole (ii)...
We conduct a combined experimental and theoretical study of the quantum-confined Stark effect in GaAs/AlGaAs quantum dots obtained with local droplet etching method. In experiment, we probe permanent electric dipole polarizability neutral positively charged excitons weakly confined GaAs by measuring their light emission under influence variable field applied along growth direction. Calculations based on configuration-interaction method show excellent quantitative agreement experiment allow...
The optical properties of excitons confined in initially unstrained GaAs/AlGaAs quantum dots are studied as a function variable quasiuniaxial stress. To allow the validation state-of-the-art computational tools for describing nanostructures, we determine dot morphology and in-plane components externally induced strain tensor at positions. Based on these experimental parameters, calculate strain-dependent excitonic emission energy, degree linear polarization, fine-structure splitting using...
Infinite-layer nickelates show high-temperature superconductivity, and the experimental phase diagram agrees well with one simulated within dynamical vertex approximation (D$\Gamma$A). Here, we compare spin-fluctuation spectrum behind these calculations to resonant inelastic X-ray scattering experiments. The overall agreement is good. This independent cross-validation of strength spin fluctuations strongly supports scenario, advanced by D$\Gamma$A, that spin-fluctuations are mediator...
The density functional plus dynamical mean-field theory is used to study the spin excitation spectra of ${\mathrm{SrRu}}_{2}{\mathrm{O}}_{6}$. A good quantitative agreement with experimental found. Depending on size Hund's coupling ${J}_{\mathrm{H}}$, system chooses either Mott insulator or covalent state when magnetic ordering not allowed. We find that nature paramagnetic has a negligible influence charge and spectra. antiferromagnetic correlations hide for realistic choices interaction parameters.
The density functional plus dynamical mean-field theory is used to study the spin excitation spectra of ${\mathrm{SrRu}}_{2}{\mathrm{O}}_{6}$. A good quantitative agreement with experimental found. Depending on size Hund's coupling ${J}_{\mathrm{H}}$, system chooses either Mott insulator or covalent state when magnetic ordering not allowed. We find that nature paramagnetic has a negligible influence charge and spectra. antiferromagnetic correlations hide for realistic choices interaction parameters.