A5001182001- Electronic and Structural Properties of Oxides
- Topological Materials and Phenomena
- Magnetic and transport properties of perovskites and related materials
- Advanced Condensed Matter Physics
- Rare-earth and actinide compounds
- Iron-based superconductors research
- 2D Materials and Applications
- Graphene research and applications
- Semiconductor materials and devices
- Physics of Superconductivity and Magnetism
- Ferroelectric and Piezoelectric Materials
- Quantum and electron transport phenomena
- Organic and Molecular Conductors Research
- Inorganic Chemistry and Materials
- Advanced Thermoelectric Materials and Devices
- Metallurgical and Alloy Processes
- Advanced Semiconductor Detectors and Materials
- Magnetic Properties of Alloys
- Magnetic properties of thin films
- Intermetallics and Advanced Alloy Properties
- Advanced Chemical Physics Studies
- Machine Learning in Materials Science
- MXene and MAX Phase Materials
- Advanced Welding Techniques Analysis
- Phase-change materials and chalcogenides
Paul Scherrer Institute
2018-2025
Technical University of Denmark
2021-2024
Swiss Light Source
2018-2023
Aarhus University
2020-2023
Technische Universität Dresden
2013-2022
Ben-Gurion University of the Negev
2021
Leibniz Institute for Solid State and Materials Research
2019-2020
St Petersburg University
2011-2016
Osipyan Institute of Solid State Physics RAS
2015
We present a soft x-ray angle-resolved photoemission spectroscopy study of overdoped high-temperature superconductors. In-plane and out-of-plane components the Fermi surface are mapped by varying angle incident photon energy. No ${k}_{z}$ dispersion is observed along nodal direction, whereas significant antinodal identified for La-based cuprates. Based on tight-binding parametrization, we discuss implications density states near van Hove singularity. Our results suggest that large electronic...
Abstract Parity‐time symmetry plays an essential role for the formation of Dirac states in semimetals. So far, all experimentally identified topologically nontrivial semimetals (DSMs) possess both parity and time reversal symmetry. The realization magnetic topological DSMs remains a major issue material research. Here, combining angle‐resolved photoemission spectroscopy with density functional theory calculations, it is ascertained that band inversion induces ground state EuCd 2 As . result,...
With the discovery and first characterization of graphene, its potential for spintronic applications was recognized immediately. Since then, an active field research has developed trying to overcome practical hurdles. One most severe challenges is find appropriate interfaces between graphene ferromagnetic layers, which are granting efficient injection spin-polarized electrons. Here, we show that grown under conditions on Co(0001) demonstrates perfect structural properties simultaneously...
Abstract The hybridization between localized 4 f electrons and itinerant in rare-earth-based materials gives rise to their exotic properties like valence fluctuations, Kondo behaviour, heavy-fermions, or unconventional superconductivity. Here we present an angle-resolved photoemission spectroscopy (ARPES) study of the lattice antiferromagnet CeRh 2 Si , where surface bulk Ce-4 spectral responses were clearly resolved. pronounced 0 peak seen for Ce terminated gets strongly suppressed spectra...
Weyl fermions as emergent quasiparticles can arise in semimetals (WSMs) which the energy bands are nondegenerate, resulting from inversion or time-reversal symmetry breaking. Nevertheless, experimental evidence for magnetically induced WSMs is scarce. Here, using photoemission spectroscopy, we observe that degeneracy of Bloch already lifted paramagnetic phase EuCd2As2. We attribute this effect to itinerant electrons experiencing quasi-static and quasi-long-range ferromagnetic fluctuations....
Collective electronic states such as the charge density wave (CDW) order and superconductivity (SC) respond sensitively to external perturbations. Such sensitivity is dramatically enhanced in two dimensions (2D), where 2D materials hosting are largely exposed environment. In this regard, ineludible presence of supporting substrates triggers various proximity effects on that may ultimately compromise stability properties ground state. work, we investigate impact CDW superconducting...
Abstract The integration of complex oxides with a wide range functionalities on conventional semiconductor platforms is highly demanded for functional applications. Despite continuous efforts to integrate Si, it still challenging harvest epitaxial layers using standard deposition processes. Here, novel method demonstrated create high‐quality heterostructures Si integrated SrTiO 3 membranes as universal platform. STO membrane successfully bridges broad spectrum such SrNbO , SrVO TiO 2 and...
Kondo lattices belong to a new class of materials defying standard concepts solid-state physics. Scientists investigate the electronic structure well-known lattice and find that Fermi surface is stable over wide range above below its temperature.
Abstract The development of materials that are non-magnetic in the bulk but exhibit two-dimensional (2D) magnetism at surface is core spintronics applications. Here, we present valence-fluctuating material EuIr 2 Si , where contrast to its bulk, Si-terminated reveals controllable 2D ferromagnetism. Close Eu ions prefer a magnetic divalent configuration and their large 4 f moments order below 48 K. emerging exchange interaction modifies spin polarization electrons originally induced by strong...
Topological semimetals with different types of band crossings provide a rich platform to realize novel fermionic excitations, known as topological fermions. In particular, some excitations can be direct analogues elementary particles in quantum field theory when both obey the same laws physics low-energy limit. Examples include Dirac and Weyl fermions, whose solid-state realizations have provided new insights into long-sought phenomena high-energy physics. Recently, theorists predicted...
Interfacing different transition-metal oxides opens a route to functionalizing their rich interplay of electron, spin, orbital, and lattice degrees freedom for electronic spintronic devices. Electronic magnetic properties SrTiO3-based interfaces hosting mobile two-dimensional electron system (2DES) are strongly influenced by oxygen vacancies, which form an dichotomy, where correlated localized electrons in the in-gap states (IGSs) coexist with noncorrelated delocalized 2DES. Here, we use...
Abstract Spin-polarized two-dimensional electron states (2DESs) at surfaces and interfaces of magnetically active materials attract immense interest because the idea exploiting fermion spins rather than charge in next generation electronics. Applying angle-resolved photoelectron spectroscopy, we show that silicon surface GdRh 2 Si bears two distinct 2DESs, one being a Shockley state other Dirac resonance. Both are subject to strong exchange interaction with ordered 4 f -moments lying...
Novel topological phases of matter are fruitful platforms for the discovery unconventional electromagnetic phenomena. Higher-fold topology is one example, where low-energy description goes beyond standard model analogs. Despite intensive experimental studies, conclusive evidence remains elusive multigap nature higher-fold chiral fermions. In this Letter, we leverage a combination fine-tuned chemical engineering and photoemission spectroscopy with photon energy contrast to discover crystal....
The electronic structure of NdTe$_3$ in the charge density wave phase (CDW) is investigated by angle-resolved photoemission spectroscopy. combination high-quality crystals and careful surface preparation reveals subtle previously unobserved details Fermi topology, allowing an interpretation rich unexplained quantum oscillations rare earth tritellurides RTe$_3$. In particular, several closed elements can be observed that are related to CDW-induced replicas original bands, leading curious...
Fermi-surface topology governs the relationship between magnetism and superconductivity in iron-based materials. Using low-temperature transport, angle-resolved photoemission, x-ray diffraction we show unambiguous evidence of large Fermi surface reconstruction CaFe$_{2}$As$_{2}$ at magnetic spin-density-wave nonmagnetic collapsed-tetragonal ($cT$) transitions. For $cT$ transition, change has a different character with no contribution from hole part surface. In addition, results suggest that...
Abstract The relationship between charge-density waves (CDWs) and superconductivity is a long-standing debate. Often observed as neighbors in phase diagrams, it still unclear whether they cooperate, compete, or simply coexist. Using angle-resolved photoemission spectroscopy, we demonstrate here that by tuning the energy position of van Hove singularity Pd-doped 2H-TaSe 2 , one able to suppress CDW enhance more than an order magnitude. We argue particular fermiology material responsible for...
We probe the local magnetic properties of interfaces between insulating ferromagnet EuS and topological insulator Bi$_2$Se$_3$ using low energy muon spin rotation (LE-$\mu$SR). compare these to interface topologically trivial metal, titanium. Below transition EuS, we detect strong fields which extend several nm into adjacent layer cause a complete depolarization muons. However, in both titanium measure similar fields, implying that their origin is mostly independent electronic states. In...
Electronic phase separation is crucial for the fascinating macroscopic properties of LaAlO3/SrTiO3 (LAO/STO) paradigm oxide interface, including coexistence superconductivity and ferromagnetism. We investigate this phenomenon using angle-resolved photoelectron spectroscopy (ARPES) in soft-X-ray energy range, where enhanced probing depth combined with resonant photoexcitation allow access to fundamental electronic structure characteristics (momentum-resolved spectral function, dispersions...
Transition metal oxides, with their wide range of electronic and magnetic properties, offer a remarkable platform for developing future electronics based on unconventional quantum phenomena, such as topological phases. The formation topologically nontrivial states is linked to crystalline symmetry, spin-orbit coupling, ordering. Here, by employing angle-resolved photoemission spectroscopy (ARPES), supported density functional theory (DFT) calculations, we demonstrated that intrinsic...