A5046432534- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Physics of Superconductivity and Magnetism
- Electronic and Structural Properties of Oxides
- Iron-based superconductors research
- Rare-earth and actinide compounds
- Multiferroics and related materials
- Ferroelectric and Piezoelectric Materials
- Magnetic properties of thin films
- Crystal Structures and Properties
- Theoretical and Computational Physics
- Atomic and Subatomic Physics Research
- Nonlocal and gradient elasticity in micro/nano structures
- Intermetallics and Advanced Alloy Properties
- Tryptophan and brain disorders
- Topological Materials and Phenomena
- High-pressure geophysics and materials
- Manufacturing Process and Optimization
- Catalysis and Oxidation Reactions
- Semiconductor materials and devices
- Inorganic Chemistry and Materials
- Inorganic Fluorides and Related Compounds
- Structural Health Monitoring Techniques
- Ferroelectric and Negative Capacitance Devices
- Superconductivity in MgB2 and Alloys
Northwest University
2011-2025
University of Vienna
2025
Institute of Theoretical Physics
2024-2025
TU Wien
2001-2024
Northwest University
2024
Foshan University
2024
China Aerospace Science and Technology Corporation
2024
Harbin Normal University
2024
Huazhong University of Science and Technology
2021-2023
Ningbo Institute of Industrial Technology
2019-2022
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...
Superconducting nickelates appear to be difficult synthesize. Since the chemical reduction of ABO_{3} [rare earth (A), transition metal (B)] with CaH_{2} may result in both ABO_{2} and ABO_{2}H, we calculate topotactic H binding energy by density functional theory (DFT). We find intercalating energetically favorable for LaNiO_{2} but not Sr-doped NdNiO_{2}. This has dramatic consequences electronic structure as determined DFT+dynamical mean field theory: that 3d^{9} is similar (doped)...
Identifying a suitable water-soluble sacrificial layer is crucial to fabricating large-scale freestanding oxide membranes, which offer attractive functionalities and integrations with advanced semiconductor technologies. Here, we introduce layer, "super-tetragonal" Sr
The discovery of infinite layer nickelate superconductor marks the new era in field superconductivity. In rare-earth (Re) nickelates ReNiO2, although Ni is also d9 electronic configuration, analogous to Cu cuprates, whether structures infinite-layer are same as cuprate and possess single band feature well still open questions. To illustrate structure nickelate, we perform first principle calculations LaNiO2 NdNiO2 compounds compare them with that CaCuO2 using hybrid functional method...
Topological insulators have attracted intensive attention due to their robust properties of path defect immunity, with diverse applications in electromagnetic, acoustic, and elastic systems. The recent development topological (ETIs), based on artificially structured phononic crystals, has injected new momentum into the manipulation waves. Earlier ETIs unreconfigurable geometry narrow frequency bandgaps hinder exploration design adaptable devices. In this work, a tunable crystal plate...
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"...
A recent paper [Lee et al., J. Kor. Cryst. Growth Technol. 33, 61 (2023)] provides some experimental indications that ${\mathrm{Pb}}_{10\ensuremath{-}x}{\mathrm{Cu}}_{x}{({\mathrm{PO}}_{4})}_{6}\mathrm{O}$ with $x\ensuremath{\approx}1$, coined LK-99, might be a room-temperature superconductor at ambient pressure. Our density-functional theory (DFT) calculations show lattice parameters and volume contraction $x$, very similar to experiment. The DFT electronic structure shows...
Motivated by cuprate and nickelate superconductors, we perform a comprehensive study of the superconducting instability in single-band Hubbard model. We calculate spectrum transition temperature T_{c} as function filling Coulomb interaction for range hopping parameters, using dynamical vertex approximation. find sweet spot high to be at intermediate coupling, moderate Fermi surface warping, low hole doping. Combining these results with first principles calculations, neither nickelates nor...
Abstract Recent progress on the signatures of pressure-induced high-temperature superconductivity in Ruddlesden–Popper (RP) nickelates (La n +1 Ni O 3 ) has attracted growing interest both theoretical calculations and experimental efforts. The fabrication high-quality single-crystalline RP nickelate thin films is critical for possible reducing superconducting transition pressure advancing applications microelectronics future. In this study, we report observations an active phase induced by...
Abstract High-temperature unconventional superconductivity quite generically emerges from doping a strongly correlated parent compound, often (close to) an antiferromagnetic insulator. The recently developed dynamical vertex approximation is state-of-the-art technique that has quantitatively predicted the superconducting dome of nickelates. Here, we apply it to study effect pressure in infinite-layer nickelate Sr x Pr 1− NiO 2 . We reproduce increase critical temperature ( T c ) under found...
Thickness driven electronic phase transitions are broadly observed in different types of functional perovskite heterostructures. However, uncertainty remains whether these effects solely due to spatial confinement, broken symmetry or rather a change structure with varying film thickness. Here, we present direct evidence for the relaxation oxygen 2p and Mn 3d orbital (p-d) hybridization coupled layer dependent octahedral tilts within La2/3Sr1/3MnO3 by interfacial coupling. An enhanced Curie...
Motivated by the recent discovery of superconductivity in pentalayer nickelate ${\mathrm{Nd}}_{6}{\mathrm{Ni}}_{5}{\mathrm{O}}_{12}$ [G. A. Pan et al., Nat. Mater. 21, 160 (2022)], we calculate its electronic structure and superconducting critical temperature. We find that correlations are essential for pushing into doping range as they shift electron pockets above Fermi energy. As a consequence, can be described with single ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ orbital per Ni. predict to...
The 2D electron gas (2DEG) at oxide interfaces exhibits extraordinary properties, such as superconductivity and ferromagnetism, coupled to strongly correlated electrons in narrow d-bands. In particular, 2DEGs KTaO
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...
In situ electrical control of the Dzyaloshinskii-Moriya interaction (DMI) is one central but challenging goals toward skyrmion-based device applications. An atomic design defective interfaces in spin-orbit-coupled transition-metal oxides can be an appealing strategy to achieve this goal. work, by utilizing distinct formation energies and diffusion barriers oxygen vacancies at SrRuO3 /SrTiO3 (001), a sharp interface constructed between oxygen-deficient stoichiometric . This interfacial...
We briefly review the status quo of research on putative superconductor Pb9Cu(PO4)6O also known as LK-99. Further, we provideab initioderived tight-binding parameters for a two- and five-band model, solve these in dynamical-mean-field theory. The interaction-to-bandwidth ratio makes LK-99 Mott or charge transfer insulator. Electron hole doping (which is different from substituting Pb by Cu thus differs LK-99) required to make it metallic potentially superconducting.
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...
Experimental efforts to stabilize ferromagnetism in ultrathin films of transition metal oxides have so far failed, despite expectations based on density functional theory (DFT) and DFT+$U$. Here, we investigate one the most promising materials, ${\mathrm{SrRuO}}_{3}$, include correlation effects beyond DFT by means dynamical mean-field theory. In agreement with experiment, find an intrinsic thickness limitation for metallic ${\mathrm{SrRuO}}_{3}$ thin films. Indeed, demonstrate that...
Light control of emergent quantum phenomena is a widely used external stimulus for materials. Generally, perovskite strontium ruthenate SrRuO3 has an itinerant ferromagnetism with low-spin state. However, the phase intermediate-spin (IS) ferromagnetic metallic state never been seen. Here, by means UV-light irradiation, photocarrier-doping-induced Mott-insulator-to-metal transition shown in few atomic layers IS SrRuO3-δ . This new metastable can be reversibly regulated due to convenient...
A recent paper [Lee {\em et al.}, J. Korean Cryt. Growth Cryst. Techn. {\bf 33}, 61 (2023)] provides some experimental indications that Pb$_{10-x}$Cu$_x$(PO$_4$)$_6$O with $x\approx 1$, coined LK-99, might be a room-temperature superconductor at ambient pressure. Our density-functional theory calculations show lattice parameters and volume contraction $x$ -- very similar to experiment. The DFT electronic structure shows Cu$^{2+}$ in $3d^9$ configuration two flat Cu bands crossing the Fermi...
Despite enormous experimental and theoretical efforts, obtaining generally accepted conclusions regarding the intrinsic magnetic electronic properties of superconducting nickelates remains exceptionally challenging. Experiments show a significant degree uncertainty, indicating hidden factors in synthesized films, which call for further investigations. One those is possibility intercalating hydrogen during chemical reduction process from $\mathrm{Nd}(\mathrm{La}){\mathrm{NiO}}_{3}$ to...
A recent experiment [X. Ding et al., Nature (London) 615, 50 (2023)] indicates that superconductivity in nickelates is restricted to a narrow window of hydrogen concentration, $0.22<x<0.28$ ${\mathrm{Nd}}_{0.8}{\mathrm{Sr}}_{0.2}{\mathrm{NiO}}_{2}{\mathrm{H}}_{x}$. This reported necessity suggests it plays crucial role for superconductivity, as does the vast field hydride superconductors. Using density-functional theory and its extensions, we explore effect topotactic on electronic structure...