A5030501605- Topological Materials and Phenomena
- Magnetic properties of thin films
- Graphene research and applications
- Electronic and Structural Properties of Oxides
- 2D Materials and Applications
- Surface and Thin Film Phenomena
- Advanced Condensed Matter Physics
- Quantum and electron transport phenomena
- Advanced Chemical Physics Studies
- Electron and X-Ray Spectroscopy Techniques
- Magnetic and transport properties of perovskites and related materials
- Physics of Superconductivity and Magnetism
- Molecular Junctions and Nanostructures
- Surface Chemistry and Catalysis
- Semiconductor materials and devices
- ZnO doping and properties
- Transition Metal Oxide Nanomaterials
- Chalcogenide Semiconductor Thin Films
- Fullerene Chemistry and Applications
- MXene and MAX Phase Materials
- Iron-based superconductors research
- Rare-earth and actinide compounds
- X-ray Spectroscopy and Fluorescence Analysis
- Quantum Dots Synthesis And Properties
- Radioactive contamination and transfer
AREA Science Park
2016-2025
Istituto Officina dei Materiali
2015-2024
National Research Council
2011-2024
Elettra-Sincrotrone Trieste S.C.p.A.
2003-2023
Think-tank for Action on Social Change
2023
Tsinghua University
2021
ShanghaiTech University
2021
Max Planck Institute for Chemical Physics of Solids
2021
Diamond Light Source
2021
University of Oxford
2021
Abstract Topological Weyl semimetal (TWS), a new state of quantum matter, has sparked enormous research interest recently. Possessing unique fermions in the bulk and Fermi arcs on surface, TWSs offer rare platform for realizing many exotic physical phenomena. can be classified into type-I that respect Lorentz symmetry type-II do not. Here, we directly visualize electronic structure MoTe 2 , recently proposed TWS. Using angle-resolved photoemission spectroscopy (ARPES), unravel surface arcs,...
Band inversions are key to stabilising a variety of novel electronic states in solids, from topological surface inverted bulk band gaps insulators the formation symmetry-protected three-dimensional Dirac and Weyl points nodal-line semimetals. Here, we create inversion not states, but rather between manifolds states. We realise this by aliovalent substitution Nb for Zr Sb S ZrSiS family nonsymmorphic Using angle-resolved photoemission density-functional theory, show how two pairs known ZrSiS,...
The layered van der Waals antiferromagnet MnBi${}_{2}$Te${}_{4}$ has been predicted previously to realize the first intrinsic magnetic topological insulator. Here, authors report spin- and angle-resolved photoemission experiments for MnBi${}_{2}$Te${}_{4}$(0001) surface, revealing a surface state in bulk band gap providing evidence interplay between exchange interaction spin-orbit coupling electronic structure. thus constitutes promising candidate exploit of states order spintronic device concepts.
Altermagnetism, a kind of collinear magnetism that is characterized by momentum-dependent band and spin splitting without net magnetization, has recently attracted considerable interest. Finding altermagnetic materials with large near the Fermi level necessarily requires three-dimensional k-space mapping. While this crucial for spintronic applications emergent phenomena, it remains challenging. Here, using synchrotron-based angle-resolved photoemission spectroscopy (ARPES), spin-resolved...
The outstanding properties of graphene, a single graphite layer, render it top candidate for substituting silicon in future electronic devices. so far exploited synthesis approaches, however, require conditions typically achieved specialized laboratories and result graphene sheets whose are often altered by interactions with substrate materials. development graphene-based technologies requires an economical fabrication method compatible mass production. Here we demonstrate the fist time...
Spin-based electronics in topological insulators (TIs) is favored by the long spin coherence(1,2) and consequently fault-tolerant information storage. Magnetically doped TIs are ferromagnetic up to 13 K,(3) well below any practical operating condition. Here we demonstrate that long-range ferromagnetism at ambient temperature can be induced Bi(2-x)Mn(x)Te(3) magnetic proximity effect through deposited Fe overlayer. This result opens a new path interface-controlled TI-based spintronic devices.
The electric and nonvolatile control of the spin texture in semiconductors would represent a fundamental step toward novel electronic devices combining memory computing functionalities. Recently, GeTe has been theoretically proposed as father compound new class materials, namely ferroelectric Rashba semiconductors. They display bulk bands with giant Rashba-like splitting due to inversion symmetry breaking arising from polarization, thus allowing for spin. Here, we provide experimental...
We report the main characteristics of advanced photoelectric effect experiments beamline, operational at Elettra storage ring, featuring a fully independent double branch scheme obtained by use chicane undulators and able to keep polarization control in both linear circular mode. The paper describes novel technical solutions adopted, namely, (a) design quasiperiodic undulator resulting optimized suppression higher harmonics over large photon energy range (10-100 eV), (b) thermal stability...
Abstract The behaviour of electrons and holes in a crystal lattice is fundamental quantum phenomenon, accounting for rich variety material properties. Boosted by the remarkable electronic physical properties two-dimensional materials such as graphene topological insulators, transition metal dichalcogenides have recently received renewed attention. In this context, anomalous bulk semimetallic WTe 2 attracted considerable interest. Here we report angle- spin-resolved photoemission spectroscopy...
Trigonal tellurium, a small-gap semiconductor with pronounced magneto-electric and magneto-optical responses, is among the simplest realizations of chiral crystal. We have studied by spin- angle-resolved photoelectron spectroscopy its unconventional electronic structure unique spin texture. identify Kramers-Weyl, composite, accordionlike Weyl fermions, so far only predicted theory, show that polarization parallel to wave vector along lines in k space connecting high-symmetry points. Our...
Abstract The zero‐magnetic‐field nonlinear Hall effect (NLHE) refers to the second‐order transverse current induced by an applied alternating electric field; it indicates topological properties of inversion‐symmetry‐breaking crystals. Despite several studies on NLHE Berry‐curvature dipole in Weyl semimetals, direct conversion rectification is limited very low driving frequencies and cryogenic temperatures. photoresponse generated at room temperature can be useful for numerous applications...
Kagome materials have emerged as a setting for emergent electronic phenomena that encompass different aspects of symmetry and topology. It is debated whether the XV$_6$Sn$_6$ kagome family (where X rare earth element), recently discovered bilayer metals, hosts topologically non-trivial ground state resulting from opening spin-orbit coupling gaps. These states would carry finite spin-Berry curvature, topological surface states. Here, we investigate spin structure family. We obtain evidence...
The relation between crystal symmetries, electron correlations, and electronic structure steers the formation of a large array unconventional phases matter, including magneto-electric loop currents chiral magnetism. Detection such hidden orders is major goal in condensed matter physics. However, to date, nonstandard forms magnetism with ordering have been experimentally elusive. Here, we develop theory for symmetry-broken ground states propose methodology based on circularly polarized...
Abstract 4Hb-TaS 2 is a superconductor that exhibits unique characteristics such as time-reversal symmetry breaking, hidden magnetic memory, and topological edge modes. It naturally occurring heterostructure comprising of alternating layers 1H-TaS 1T-TaS . The former well-known superconductor, while the latter correlated insulator with possible non- trivial ground state. In this study, we use angle resolved photoemission spectroscopy to investigate normal state electronic structure...
A peculiar Rashba effect is found at a point in the Brillouin zone, where time-reversal symmetry broken, though this was believed to be necessary condition for splitting. This finding obtained experimentally by photoemission measurements on $\mathrm{Bi}/\mathrm{Si}(111)\mathrm{\text{\ensuremath{-}}}(\sqrt{3}\ifmmode\times\else\texttimes\fi{}\sqrt{3})$ surface fully confirmed first-principles theoretical calculation. We that simply understood two-dimensional of surface, and leads an...
In the present photoemission study of a cuprate superconductor Bi1.74Pb0.38Sr1.88CuO6+delta, we discovered large scale dispersion lowest band, which unexpectedly follows band structure calculation very well. Similar behavior observed in blue bronze and Mott insulator Ca2CuO2Cl2 suggests that origin hopping-dominated an overdoped might be quite complicated. A giant kink is observed, complete self-energy containing all interaction information extracted for doped cuprate. These results...
Angle resolved photoelectron spectroscopy (ARPES) is extensively used to characterize the dependence of electronic structure graphene on Ir(111) preparation process. ARPES findings reveal that temperature programmed growth alone or in combination with chemical vapor deposition leads displaying sharp bands. The photoemission intensity Dirac cone monitored as a function increasing area. Electronic features moir\'e superstructure present system, namely minigaps and replica bands are examined...
We present a study on the growth and characterization of high-quality single-layer MoS2 with single orientation, i.e. without presence mirror domains. This orientation layer is established by means x-ray photoelectron diffraction. The high quality evidenced combining scanning tunneling microscopy spectroscopy measurements. Spin- angle-resolved photoemission experiments performed sample revealed complete spin-polarization valence band states near K -K points Brillouin zone. These findings...
We predict ${\mathrm{NiTe}}_{2}$ to be a type-II Dirac semimetal based on ab initio calculations and explore its bulk spin-polarized surface states using spin- angle-resolved photoemission spectroscopy (spin-ARPES). Our results show that, unlike ${\mathrm{PtTe}}_{2}, {\mathrm{PtSe}}_{2}$, ${\mathrm{PdTe}}_{2}$, the node in is located close vicinity Fermi energy. Additionally, also hosts pair of band inversions below level along $\mathrm{\ensuremath{\Gamma}}\ensuremath{-}A$ high-symmetry...
Topological insulators are a promising class of materials for applications in the field spintronics. New perspectives this can arise from interfacing metal–organic molecules with topological insulator spin-momentum locked surface states, which be perturbed enhancing or suppressing spintronics-relevant properties such as spin coherence. Here we show results an angle-resolved photemission spectroscopy (ARPES) and scanning tunnelling microscopy (STM) study prototypical cobalt phthalocyanine...
By combining bulk sensitive soft-x-ray angular-resolved photoemission spectroscopy and first-principles calculations we explored the electron states of WTe_{2}, a candidate type-II Weyl semimetal featuring large nonsaturating magnetoresistance. Despite layered geometry suggesting two-dimensional electronic structure, directly observe three-dimensional dispersion. We report band dispersion in reciprocal direction perpendicular to layers, implying that electrons can also travel coherently when...