A5078910452- Advanced Condensed Matter Physics
- Physics of Superconductivity and Magnetism
- Magnetic and transport properties of perovskites and related materials
- Multiferroics and related materials
- Magnetic properties of thin films
- Topological Materials and Phenomena
- Iron-based superconductors research
- Magnetism in coordination complexes
- Rare-earth and actinide compounds
- Crystal Structures and Properties
- Electronic and Structural Properties of Oxides
- Theoretical and Computational Physics
- 2D Materials and Applications
- Inorganic Fluorides and Related Compounds
- Inorganic Chemistry and Materials
- Atomic and Subatomic Physics Research
- Superconductivity in MgB2 and Alloys
- Geological and Geophysical Studies
- Organic and Molecular Conductors Research
- Graphene research and applications
- Catalysis and Oxidation Reactions
- Quantum and electron transport phenomena
- Magneto-Optical Properties and Applications
- High-pressure geophysics and materials
- Perovskite Materials and Applications
Leibniz Institute for Solid State and Materials Research
2019-2025
The University of Tokyo
2024
TU Wien
2016-2019
Max Planck Institute for Chemical Physics of Solids
2007-2016
National Institute of Chemical Physics and Biophysics
2013-2016
Max Planck Society
2007-2015
St Petersburg University
2007
Following the discovery of superconductivity in cuprates and seminal work by Anderson, theoretical efforts to understand high-temperature have been focusing a large extent on simple model: one-band Hubbard model. However, superconducting need be doped, doped holes go into oxygen orbitals. This requires more elaborate multi-band model such as three-orbital Emery The recently discovered nickelate superconductors appear, at first glance, even complicated multi-orbital systems. Here, we analyse...
The natural mineral azurite Cu(3)(CO(3))(2)(OH)(2) is a frustrated magnet displaying unusual and controversially discussed magnetic behavior. Motivated by the lack of unified description for this system, we perform theoretical study based on density functional theory as well state-of-the-art numerical many-body calculations. We propose an effective generalized spin-1/2 diamond chain model which provides consistent experiments: low-temperature magnetization, inelastic neutron scattering,...
We review the electronic structure of nickelate superconductors with and without effects correlations. As a minimal model, we identify one-band Hubbard model for Ni 3 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"...
Wannier functions are a powerful tool for the determination of topological properties solids based on band structure calculations. Here, authors present simple and efficient scheme to obtain symmetry-conserving especially suitable local orbital codes. They analyze which approximation basis contribution Berry connection curvature matrices preserves symmetry argue Bloch function gauge is best suited model systems, where not explicitly known.
We report on band-structure calculations and a microscopic model of the low-dimensional magnet $\ensuremath{\beta}{\text{-Cu}}_{2}{\text{V}}_{2}{\text{O}}_{7}$. Magnetic properties this compound can be described by spin-$\frac{1}{2}$ anisotropic honeycomb lattice with averaged coupling ${\overline{J}}_{1}=60--66\text{ }\text{K}$. The low symmetry crystal structure leads to two inequivalent couplings ${J}_{1}$ ${J}_{1}^{\ensuremath{'}}$ but weak spatial anisotropy does not affect essential...
The recently discovered natural minerals ${\mathrm{Cu}}_{3}\mathrm{Zn}(\mathrm{OH}{)}_{6}{\mathrm{Cl}}_{2}$ and ${\mathrm{Cu}}_{3}\mathrm{Mg}(\mathrm{OH}{)}_{6}{\mathrm{Cl}}_{2}$ are spin $1/2$ systems with an ideal kagome geometry. Based on electronic structure calculations, we develop a realistic model which includes couplings across the hexagons beyond original that intrinsic in real materials. Exact diagonalization studies for derived reveal strong impact of these magnetic ground state....
Motivated by recent experiments on volborthite single crystals showing a wide 1/3-magnetization plateau, we perform microscopic modeling means of density functional theory (DFT) with the single-crystal structural data as starting point. Using DFT+U, find four leading magnetic exchanges: antiferromagnetic J and J2, well ferromagnetic J' J1. Simulations derived spin Hamiltonian show good agreement experimental low-field susceptibility high-field magnetization data. The 1/3-plateau phase...
SrRuO$_3$ heterostructures grown in the (111) direction are a rare example of thin film ferromagnets. By means density functional theory plus dynamical mean field we show that half-metallic ferromagnetic state with an ordered magnetic moment 2$\mu_{B}$/Ru survives ultimate dimensional confinement down to bilayer, even at elevated temperatures 500$\,$K. In minority channel, spin-orbit coupling opens gap linear band crossing corresponding $\frac34$ filling $t_{2g}$ shell. We demonstrate...
Abstract Many unusual and promising properties have been reported recently for the transition metal trichalcogenides of type M PS 3 ( = V, Mn, Fe, Ni ...), such as maintaining magnetic order to atomically thin limit, ultra-sharp many-body excitons, metal-insulator transitions and, especially Fe 2 P S 6 , giant linear dichroism among others. Here we conduct a detailed investigation electronic structure using angle-resolved photoemission spectroscopy, q -dependent electron energy loss optical...
The presence of magnetism in potentially altermagnetic <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>RuO</a:mi><a:mn>2</a:mn></a:msub></a:math> has been a subject intense debate. Using broadband infrared spectroscopy combined with density-functional band-structure calculations, we show that the optical conductivity <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:msub><b:mi>RuO</b:mi><b:mn>2</b:mn></b:msub></b:math>, bulk probe its electronic structure, is best...
We report on studies of the superconducting and normal state properties noncentrosymmetric superconductor BeAu under hydrostatic pressure conditions. The room-temperature equation (EOS) reveals values bulk modulus ($B_0$) its first derivative ($B^\prime_0$) at ambient to be $B_0 \simeq 132$~GPa $B^\prime_0 30$, respectively. Up highest pressures studied ($p 2.2$~GPa), remains a multi-gap type-I superconductor. analysis $B_{\rm c}(T, p)$ data within self-consistent two-gap approach suggests...
Following the successful prediction of superconducting phase diagram for infinite-layer nickelates, here we calculate $T_{\mathrm{c}}$ vs. number layers $n$ finite-layer nickelates using dynamical vertex approximation. To this end, start with density functional theory, and include local correlations non-perturbatively by mean-field theory $n=2$ to 7. For all $n$, Ni $d_{x^2-y^2}$ orbital crosses Fermi level, but $n>4$ there are additional $(\pi, \pi)$ pockets or tubes that slightly enhance...
We report on studies of the superconducting and normal-state properties noncentrosymmetric superconductor BeAu under hydrostatic pressure conditions. The room-temperature equation state (EOS) reveals values bulk modulus (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>B</a:mi><a:mn>0</a:mn></a:msub></a:math>) its first derivative (<b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:msubsup><b:mi>B</b:mi><b:mn>0</b:mn><b:mo>′</b:mo></b:msubsup></b:math>) at ambient to...
We derive and investigate the microscopic model of quantum magnet BiCu2PO6 using band structure calculations, magnetic susceptibility high-field magnetization measurements, as well ED DMRG techniques. The resulting quasi-one-dimensional spin is a two-leg AFM ladder with frustrating next-nearest-neighbor couplings along legs. individual are estimated from calculations by fitting theoretical predictions, obtained ED. nearest-neighbor leg coupling J1, rung J4, one J2 amount to 120-150 K, while...
We report on the microscopic magnetic modeling of spin-1/2 copper mineral malachite at ambient and elevated pressures. Despite layered crystal structure this mineral, ambient-pressure susceptibility magnetization data can be well described by an unfrustrated quasi-one-dimensional model. Weakly interacting antiferromagnetic alternating spin chains are responsible for a large gap 120K. Although intradimer Cu-O-Cu bridging angles considerably smaller than interdimer angles, density functional...
The spin-1/2 alternating Heisenberg chain system ${\mathrm{Na}}_{3}{\mathrm{Cu}}_{2}{\mathrm{SbO}}_{6}$ features two relevant exchange couplings: ${J}_{1a}$ within the structural Cu${}_{2}$O${}_{6}$ dimers and ${J}_{1b}$ between dimers. Motivated by controversially discussed nature of ${J}_{1a}$, we perform extensive density-functional-theory (DFT) calculations, including DFT + $U$ hybrid functionals. Fits to experimental magnetic susceptibility using high-temperature series expansions...
A microscopic magnetic model for $\ensuremath{\alpha}$-Cu${}_{2}$P${}_{2}$O${}_{7}$ is evaluated in a combined theoretical and experimental study. Despite dominant intradimer coupling ${J}_{1}$, sizable interdimer couplings enforce long-range ordering at ${T}_{N}=27$ K. The spin compared to the models of isostructural $\ensuremath{\beta}$-Cu${}_{2}$V${}_{2}$O${}_{7}$ $\ensuremath{\alpha}$-Cu${}_{2}$As${}_{2}$O${}_{7}$ systems. As surprise, coupled dimers alternating chains contrast with...
The first binary phase in the system Co-Bi was obtained by high-pressure high-temperature synthesis. NiBi3-type structure motif comprises cobalt-centered monocapped bismuth prisms with covalent interactions. polyhedra are condensed into infinite columns (see picture), which arranged form of a distorted hexagonal rod packing. new compound is superconductor Tc slightly below 0.5 K. As service to our authors and readers, this journal provides supporting information supplied authors. Such...
Novel Cu2+-based compounds PbCu2(SeO3)2Cl2 (space group C2/c; a = 13.056(1) Å; b 9.5567(9) c 6.9006(6) β 90.529(7)°; RI 0.0371) and PbCu2(TeO3)2Cl2 P21; 7.2401(2) 7.2688(2) 8.2846(2) 96.416(2)°; 0.0570) have been obtained by solid-state synthesis. Their crystal structures are remarkably dissimilar underlie very different magnetic behavior. While can be well described spin-chain model with an exchange coupling of J1 ≃ 160 K, is spin-dimer system that, however, features comparable...
Abstract Spin Hall effect (SHE) has its special position in spintronics. To gain new insight into SHE and to identify materials with substantial spin conductivity (SHC), we performed high-precision high-throughput ab initio calculations of the intrinsic SHC for over 20,000 nonmagnetic crystals. The revealed a strong relationship between magnitude crystalline symmetry, where large is typically associated mirror symmetry-protected nodal line band structures. This database includes 11 an...