Publication

Clocking the Melting Transition of Charge and Lattice Order in 1T-TaS2 with Ultrafast Extreme-Ultraviolet Angle-Resolved Photoemission Spectroscopy

Related publications (32)

Direct measurement of key exciton properties: Energy, dynamics, and spatial distribution of the wave function

Excitons, Coulomb-bound electron-hole pairs, are the fundamental excitations governing the optoelectronic properties of semiconductors. Although optical signatures of excitons have been studied extensively, experimental access to the excitonic wave functio ...

Wiley2021

Resonant Inelastic X-ray Scattering Studies of Low-Dimensional and Frustrated 3d Transition-Metal Oxides

Yi Tseng

3d transition-metal oxide materials with strong electron correlations and low dimensionality give rise to emerging exotic phases. Resonant inelastic X-ray scattering (RIXS) has developed as a powerful spectroscopic tool for probing the collective excitatio ...

EPFL2021

Spectroscopic view of ultrafast charge carrier dynamics in single- and bilayer transition metal dichalcogenide semiconductors

Jens Christian Johannsen

The quasiparticle spectra of atomically thin semiconducting transition metal dichalcogenides (TMDCs) and their response to an ultrafast optical excitation critically depend on interactions with the underlying substrate. Here, we present a comparative time- ...

ELSEVIER2021

Hidden bulk and surface effects in the spin polarization of the nodal-line semimetal ZrSiTe

Helmuth Berger, Marco Grioni, Arnaud Magrez, Oleg Yazyev, Alberto Crepaldi, Mauro Fanciulli, Gianmarco Gatti, Daniel Gosalbez Martinez, Silvan Dino Marcos Roth

Local inversion symmetry breaking in centrosymmetric materials can lead to large spin polarization of the electronic band structure in separate sectors of the unit cell. Here, the authors reveal such hidden spin polarisation in ZrSiTe using spin and angle ...

NATURE RESEARCH2021

Magnonic crystals with reconfigurable magnetic defects for spin-based microwave electronics

Korbinian Baumgärtl

Collective spin excitations can propagate in magnetically ordered materials in the form of waves. These so-called spin waves (SWs) or magnons are promising for low-power beyond-CMOS information processing, which does not rely anymore on the lossy movement ...

EPFL2021

Light-Induced Renormalization of the Dirac Quasiparticles in the Nodal-Line Semimetal ZrSiSe

Helmuth Berger, Philippe Bugnon, Marco Grioni, Majed Chergui, Arnaud Magrez, Luca Moreschini, Alberto Crepaldi, Simon Karl Moser, Gianmarco Gatti, Serhii Polishchuk, Michele Puppin

In nodal-line semimetals, linearly dispersing states form Dirac loops in the reciprocal space with a high degree of electron-hole symmetry and a reduced density of states near the Fermi level. The result is reduced electronic screening and enhanced correla ...

2020

Electrons leave the flatland: out-of-plane charge dynamics in layered materials

Edoardo Martino

The goal of this thesis is to explore the "neglected" third dimension of layered materials, by studying the interlayer charge dynamics through dc conductivity, optical spectroscopy and ab-initio calculations. This project was designed to respond to the gro ...

EPFL2020

Quantum interference effects of out-of-plane confinement on two-dimensional electron systems in oxides

Emmanouil Frantzeskakis, Ji Dai

It was recently discovered that a conductive, metallic state is formed on the surface of some insulating oxides. First observed on SrTiO3 (001), it was then found in other compounds as diverse as anatase TiO2, KTaO3, BaTiO3, ZnO, and also on different surf ...

2020

Evidence of Large Polarons in Photoemission Band Mapping of the Perovskite Semiconductor CsPbBr3

Marco Grioni, Majed Chergui, Alberto Crepaldi, Nicola Marzari, Nicola Colonna, Gianmarco Gatti, Serhii Polishchuk, Thomas Roland Barillot, Michele Puppin, Riccardo De Gennaro, Matthias Wolf

Lead-halide perovskite (LHP) semiconductors are emergent optoelectronic materials with outstanding transport properties which are not yet fully understood. We find signatures of large polaron formation in the electronic structure of the inorganic LHP CsPbB ...

AMER PHYSICAL SOC2020

Role of a higher-dimensional interaction in stabilizing charge density waves in quasi-one-dimensional NbSe3 revealed by angle-resolved photoemission spectroscopy

Christophe Berthod, Helmuth Berger

We revisit charge density wave (CDW) behavior in the archetypal quasi-one-dimensional (quasi-1D) material NbSe3 by high-resolution angle-resolved photoemission spectroscopy measurements utilizing a microfocused laser with a photon energy of 6.3 eV. We pres ...

2020

Oxidation States, Thouless' Pumps, and Nontrivial Ionic Transport in Nonstoichiometric Electrolytes

Federico Grasselli

Thouless' quantization of adiabatic particle transport permits one to associate an integer topological charge with each atom of an electronically gapped material. If these charges are additive and independent of atomic positions, they provide a rigorous de ...

American Physical Society2020

Terahertz surface modes and electron-phonon coupling on Bi2Se3(111)

Davide Campi

We present a combined experimental and theoretical study of the surface vibrational modes of the topological insulator Bi2Se3 with particular emphasis on the low-energy region below 10 meV that has been difficult to resolve experimentally. By applying inel ...

AMER PHYSICAL SOC2020