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Concept

Semimétal

Publications associées (30)

Orbital-Resolved DFT plus U for Molecules and Solids

Nicola Marzari, Iurii Timrov

We present an orbital-resolved extension of the Hubbard U correction to density-functional theory (DFT). Compared to the conventional shell-averaged approach, the prediction of energetic, electronic and structural properties is strongly improved, particula ...

Amer Chemical Soc2024

Electronic Coupling of Metal-to-Insulator Transitions in Nickelate-Based Heterostructures

Duncan Thomas Lindsay Alexander, Bernat Mundet

In rare earth nickelates, the metal-to-insulator transition observed as a function of temperature can be described using an electronic and a structural order parameter. The electronic one is linked to the electronic disproportionation observed below the tr ...

WILEY2023

Metal-insulator transition in composition-tuned nickel oxide films

Duncan Thomas Lindsay Alexander, Bernat Mundet

Thin films of the solid solution Nd1-xLaxNiO3 are grown in order to study the expected 0 K phase transitions at a specific composition. We experimentally map out the structural, electronic and magnetic properties as a function of x and a discontinuous, pos ...

IOP Publishing Ltd2023

Momentum-Space Imaging of Ultra-Thin Electron Liquids in δ-Doped Silicon

Gabriel Aeppli

Two-dimensional dopant layers (δ-layers) in semiconductors provide the high-mobility electron liquids (2DELs) needed for nanoscale quantum-electronic devices. Key parameters such as carrier densities, effective masses, and confinement thicknesses for 2DELs ...

WILEY2023

Competition between Carrier Injection and Structural Distortions in Electron-Doped Perovskite Nickelate Thin Films

Duncan Thomas Lindsay Alexander, Bernat Mundet

The discovery of superconductivity in doped infinite-layer nickelate thin films has brought increased attention to the behavior of the doped perovskite phase. Despite this interest, the majority of existing studies pertain to hole-doped perovskite rare-ear ...

WILEY2023

Murunskite - a new class of functional material

Davor Tolj

The subject of the present work is discovery and in-depth characterization of a new class of functional materials. Tuning of the bond polarity and orbital occupation with a goal of establishing balance between localization and delocalization of electrons - ...

EPFL2023

Complementary screening for quantum spin Hall insulators in two-dimensional exfoliable materials

Nicola Marzari, Davide Campi, Antimo Marrazzo, Davide Grassano

Quantum spin Hall insulators are a class of topological materials that has been extensively studied during the past decade. One of their distinctive features is the presence of a finite band gap in the bulk and gapless, topologically protected edge states ...

Amer Physical Soc2023

Atomic-scale Characterization of Strain and Gate effects on Two-dimensional Materials by Scanning Tunneling Microscopy

Jz -Yuan Juo

Strain is an inevitable phenomenon in two-dimensional (2D) material, regardless of whether the film is suspended or supported. Moreover, strain is known to alter the physical and chemical properties, such as the band gap, charge carrier effective masses, d ...

EPFL2023

Phase transition of layer-stacked borophene under pressure

Oleg Yazyev, Quansheng Wu

The 8-Pmmn borophene, a boron analog of graphene, hosts tilted and anisotropic massless Dirac fermion quasiparticles owing to the presence of a distorted graphenelike sublattice. First-principles calculations show that stacked 8-Pmmn borophene is transform ...

AMER PHYSICAL SOC2022

Anisotropic and nonlinear transport in microstructured 3D topological semimetals

Xiangwei Huang

Topological semimetals are frequently discussed as materials platforms for future electronics that exploit the remarkable properties of their quasiparticles. These ideas are mostly based on dispersion relations that mimic relativistic particles, such as We ...

EPFL2022

Anti-Jahn-Teller effect induced ultrafast insulator to metal transition in perovskite BaBiO3

Changpeng Lin

The Jahn-Teller (JT) effect involves the ions M with a degenerate electronic state distorting the corner-sharing MO6 octahedra to lift the degeneracy, inducing strong coupling of electrons to lattice, and mediating the exotic properties in perovskite oxide ...

NATURE PORTFOLIO2022

Single-Walled Black Phosphorus Nanotube as a NO(2 )Gas Sensor

Xiao Zhou

An ab initio density functional theory study on the candidacy of single-walled black phosphorus nanotubes (BPNTs) towards sensing several common toxic gas molecules (NH3, CO, NO, NO2, and SO2) was conducted. Various adsorption characteristics, including th ...

ELSEVIER2022

Many-body Green?s function approach to lattice thermal transport

Nicola Marzari, Michele Simoncelli

Recent progress in understanding thermal transport in complex crystals has highlighted the prominent role of heat conduction mediated by interband tunneling processes, which emerge between overlapping phonon bands (i.e., with energy differences smaller tha ...

AMER PHYSICAL SOC2022

Machines for Materials and Materials for Machines: Metal-Insulator Transitions and Artificial Intelligence

Bernat Mundet

In this perspective, we discuss the current and future impact of artificial intelligence and machine learning for the purposes of better understanding phase transitions, particularly in correlated electron materials. We take as a model system the rare-eart ...

2021

Extremely large magnetoresistance in the "ordinary" metal ReO3

Oleg Yazyev, Quansheng Wu, Shengnan Zhang

The extremely large magnetoresistance (XMR) observed in many topologically nontrivial and trivial semimetals has attracted much attention in relation to its underlying physical mechanism. In this paper, by combining the band structure and Fermi surface (FS ...

AMER PHYSICAL SOC2021

Proximity-Induced Novel Ferromagnetism Accompanied with Resolute Metallicity in NdNiO3 Heterostructure

Joël Mesot, Zoran Ristic, Marco Caputo

Employing X-ray magnetic circular dichroism (XMCD), angle-resolved photoemission spectroscopy (ARPES), and momentum-resolved density fluctuation (MRDF) theory, the magnetic and electronic properties of ultrathin NdNiO3 (NNO) film in proximity to ferromagne ...

2021

Magnetic electron collimation in three-dimensional semi-metals

Philip Johannes Walter Moll, Matthias Carsten Putzke, Chunyu Guo, Xiangwei Huang, Jonas De Jesus Diaz Gomez

While electrons moving perpendicular to a magnetic field are confined to cyclotron orbits, they can move freely parallel to the field. This simple fact leads to complex current flow in clean, low carrier density semi-metals, such as long-ranged current jet ...

2020

Temperature dependence of reconfigurable bandstop filters using vanadium dioxide switches

Mihai Adrian Ionescu, Matteo Cavalieri, Andrei Müller

In this Letter, we report and investigate the temperature dependency of various radio frequency (RF) parameters for a fabricated reconfigurable bandstop filter with vanadium dioxide (VO2) switches measured up to 55 GHz. Here, the insulator-to-metal (ITM) a ...

AIP American Institute of Physics2020

Length scales of interfacial coupling between metal and insulator phases in oxides

Duncan Thomas Lindsay Alexander, Bernat Mundet

The characteristic length scale and mechanism of the metal-insulator transition in nickelate superlattices is addressed, with implications for the design of oxide electronics. ...

NATURE PUBLISHING GROUP2020

Electronic structure of pristine and Ni-substituted LaFeO3 from near edge x-ray absorption fine structure experiments and first-principles simulations

Nicola Marzari, Iurii Timrov, Matteo Cococcioni, Xinyu Zhang, Piyush Agrawal

We present a joint theoretical and experimental study of the oxygen K-edge spectra for LaFeO3 and homovalent Ni-substituted LaFeO3 (LaFe0.75Ni0.25O3), using first-principles simulations based on density-functional theory with extended Hubbard functionals a ...

AMER PHYSICAL SOC2020