Publications related to An innovative Yb-based ultrafast deep ultraviolet source for time-resolved photoemission experiments

Field-induced ultrafast modulation of Rashba coupling at room temperature in ferroelectric alpha-GeTe(111)

Rashba materials have appeared as an ideal playground for spin-to-charge conversion in prototype spintronics devices. Among them, alpha-GeTe(111) is a non-centrosymmetric ferroelectric semiconductor for which a strong spin-orbit interaction gives rise to g ...

Nature Portfolio2022

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

Photo- and thermally-induced electronic and structural dynamics in perovskites and transition metal oxides

Oliviero Cannelli

In this thesis, we exploited optical and X-ray pump-probe methods in a synergistic approach to study the interplay of the electronic, spin and structural degrees of freedom in two class of complex systems relevant for solar energy conversion applications: ...

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

Excited-state band mapping and momentum-resolved ultrafast population dynamics in In/Si(111) nanowires investigated with XUV-based time- and angle-resolved photoemission spectroscopy

Michele Puppin, Matthias Wolf

We investigate the excited state electronic structure of the model phase transition system In/Si(111) using femtosecond time-and angle-resolved photoemission spectroscopy (trARPES). An extreme ultraviolet 500 kHz laser source at 21.7 eV is utilized both to ...

AMER PHYSICAL SOC2019

Unveiling the electronic transformations in the semi-metallic correlated-electron transitional oxide Mo8O23

Marco Grioni, Gianmarco Gatti

Mo8O23 is a low-dimensional chemically robust transition metal oxide coming from a prospective family of functional materials, MoO3-x, ranging from a wide gap insulator (x = 0) to a metal (x = 1). The large number of stoichometric compounds with intermedia ...

Nature Research2019

Spin polarization and attosecond time delay in photoemission from solids

Mauro Fanciulli

In the photoemission process electrons are emitted from a solid upon excitation with UV light. From the measurement of their energy and momentum, angle-resolved photoemission spectroscopy (ARPES) allows to reconstruct the electronic properties of the solid ...

EPFL2018

Charge-carrier Dynamics in Metal Oxides and Hybrid Lead Perovskites investigated by Time-Resolved UV and X-ray Spectroscopy

Thomas Charles Henry Rossi

In modern ultrafast optoelectronic technologies based on wide band gap insulators, the non-equilibrium dynamics of photogenerated charges plays a major role. Unravelling the mechanisms of interaction between these charge carriers and their environment is c ...

EPFL2018

Spin Polarization and Attosecond Time Delay in Photoemission from Spin Degenerate States of Solids

Stefan Peter Muff, Jan Hugo Dil, Mauro Fanciulli

After photon absorption, electrons from a dispersive band of a solid require a finite time in the photoemission process before being photoemitted as free particles, in line with recent attosecond-resolved photoemission experiments. According to the Eisenbu ...

American Physical Society2017

Time-resolved ARPES at LACUS: Band Structure and Ultrafast Electron Dynamics of Solids

Helmuth Berger, Philippe Bugnon, Marco Grioni, Majed Chergui, Frank van Mourik, Arnaud Magrez, Christopher Alexander Arrell, Alberto Crepaldi, José Javier Pancracio Ojeda Andara, Gianmarco Gatti, Silvan Dino Marcos Roth

The manipulation of the electronic properties of solids by light is an exciting goal, which requires knowledge of the electronic structure with energy, momentum and temporal resolution. Time- and angle-resolved photoemission spectroscopy (tr-ARPES) is the ...

2017

Bulk diffusive relaxation mechanisms in optically excited topological insulators

Helmuth Berger, Philippe Bugnon, Arnaud Magrez, Alberto Crepaldi

The possibility to inject spin currents in topological insulators (TIs) by ultrashort optical pulses has stimulated intense studies of their out-of-equilibrium electronic properties. However, a comprehensive description of the electronic relaxation dynamic ...

Amer Physical Soc2017

Watching ultrafast responses of structure and magnetism in condensed matter with momentum-resolved probes

Paul Beaud, Fabrizio Carbone

We present a non-comprehensive review of some representative experimental studies in crystalline condensed matter systems where the effects of intense ultrashort light pulses are probed using x-ray diffraction and photoelectron spectroscopy. On an ultrafas ...

2017

Ultrafast Photoelectron Spectroscopy of Liquid Samples

José Javier Pancracio Ojeda Andara

This thesis focuses on the commissioning and characterization of HARMONIUM, an ultrafast tunable EUV source based on high-harmonic generation for performing photoelectron spectroscopy of liquids. In ultrafast photoelectron spectroscopy a short pump pulse i ...

EPFL2016

Revealing the role of electrons and phonons in the ultrafast recovery of charge density wave correlations in 1T-TiSe2

Helmuth Berger, Arnaud Magrez, Matthias Wolf

Using time-and angle-resolved photoemission spectroscopy with selective near-and midinfrared photon excitations, we investigate the femtosecond dynamics of the charge density wave ( CDW) phase in 1T-TiSe2 as well as the dynamics of CDW fluctuations at 240 ...

Amer Physical Soc2016

First-Principles Photoemission Spectroscopy of DNA and RNA Nucleobases from Koopmans-Compliant Functionals

Nicola Marzari, Giovanni Borghi, Andrea Ferretti

The need to interpret ultraviolet photoemission data strongly motivates the refinement of first-principles techniques that are able to accurately predict spectral properties. In this work, we employ Koopmans-compliant functionals, constructed to enforce pi ...

Amer Chemical Soc2016

Ramifications of optical pumping on the interpretation of time-resolved photoemission experiments on graphene

Marco Grioni, Alberto Crepaldi, Jens Christian Johannsen

In pump-probe time and angle-resolved photoemission spectroscopy (TR-ARPES) experiments the presence of the pump pulse adds a new level of complexity to the photoemission process in comparison to conventional ARPES. This is evidenced by pump-induced vacuum ...

Elsevier Science Bv2015

Interplay between electronic and structural properties in the Pb/Ag(100) interface

Marco Grioni, Alberto Crepaldi, Simon Karl Moser

We report an investigation of the structural and electronic properties of a Pb monolayer (ML) grown on Ag(1 0 0), by combining x-ray photoelectron diffraction (XPD) and angle resolved photoelectron spectroscopy (ARPES). The Pb atoms are found to arrange in ...

Iop Publishing Ltd2015

Ultrafast Photophysics of Transition Metal Complexes

Majed Chergui

CONSPECTUS: The properties of transition metal complexes are interesting not only for their potential applications in solar energy conversion, OLEDs, molecular electronics, biology, photochemistry, etc. but also for their fascinating photophysical properti ...

American Chemical Society2015

Ultrafast electron dynamics in epitaxial graphene investigated with time- and angle-resolved photoemission spectroscopy

Marco Grioni, Alberto Crepaldi, Jens Christian Johannsen

In order to exploit the intriguing optical properties of graphene it is essential to gain a better understanding of the light-matter interaction in the material on ultrashort timescales. Exciting the Dirac fermions with intense ultrafast laser pulses trigg ...

Iop Publishing Ltd2015

Ultrafast Optical Control of the Electronic Properties of ZrTe5

Helmuth Berger, Philippe Bugnon, Marco Grioni, Arnaud Magrez, Alberto Crepaldi

We report on the temperature dependence of the ZrTe5 electronic properties, studied at equilibrium and out of equilibrium, by means of time and angle resolved photoelectron spectroscopy. Our results unveil the dependence of the electronic band structure ac ...

Amer Physical Soc2015