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Marco Grioni

Cette personne a quitté l’EPFL

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Publications associées (109)

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Momentum and photon energy dependence of the circular dichroic photoemission in the bulk Rashba semiconductors BiTeX (X = I, Br, Cl)

Helmuth Berger, Arnaud Magrez, Marco Grioni, Oleg Yazyev, Philippe Bugnon, Alberto Crepaldi, Luca Moreschini, Gabriel Albert Autes, Jens Christian Johannsen, Cédric Tournier-Colletta

Bulk Rashba systems BiTeX (X = I, Br, Cl) are emerging as important candidates for developing spintronics devices because of the coexistence of spin-split bulk and surface states, along with the ambipolar character of the surface charge carriers. The need ...

American Physical Society2014

Observation of filled states at the Fermi-level in alkali-metal intercalated organic films: dependence on substrate work function

Marco Grioni

We present ultraviolet photoelectron spectroscopy studies on alkali metal-intercalated thin films of electroluminescent p-sexiphenyl (6P) and the organic hole transporting material N,N'-bis-(1-naphthyl)-N,N'-diphenyll-1,1-biphenyl1-4,4'-diamine (alpha-NPD) ...

Elsevier2005

Volatile two-dimensional electron gas in ultrathin BaTiO3 films

Marco Grioni, Simon Karl Moser, Luca Moreschini, Sara Fatale

We investigate the metallic surface state in ultrathin films of BaTiO3 by angle-resolved photoemission spectroscopy. We find Fermi-surface contours derived from the Ti 3d t(2g) conduction band, similar as in SrTiO3 but with broader spectral features due to ...

AMER PHYSICAL SOC2018

Low-temperature spin-state transition in LaCoO3 investigated using resonant x-ray absorption at the CoK edge

Marco Grioni

LaCoO3 displays two broad anomalies in the DC magnetic susceptibility chi(DC), occurring, respectively, around 50 K and 500 K. We have investigated the first of them within the 10 K < T < RT temperature range using Co K alpha(1) x-ray absorption spectrosco ...

2006

Orbital selective overlayer-substrate hybridization in a Pb monolayer on Ag(111)

Klaus Kern, Frédéric Mila, Harald Brune, Marco Grioni, Thomas Gloor, Stephan Fedrigo

The electronic structure of a Pb overlayer on Ag(111) has been studied by angle-resolved photoemission spectroscopy. We identify three p bands. While the p(xy) bands are sharp and closely resemble the corresponding bands of a free-standing Pb layer, the p( ...

2006

Polarization dependence of angle-resolved photoemission with submicron spatial resolution reveals emerging one-dimensionality of electrons in NbSe3

Miguel Angel Valbuena, Helmuth Berger, Marco Grioni, Emmanouil Frantzeskakis

In materials with nearly commensurate band filling the electron liquid may spontaneously separate into components with distinct properties, yielding complex intra- and interunit cell ordering patterns and a reduced dimensionality. Polarization-dependent an ...

AMER PHYSICAL SOC2019

Electronic structure of one-dimensional copper oxide chains in LiCu2O2 from angle-resolved photoemission and optical spectroscopy

Helmuth Berger, Marco Grioni

Angle-resolved photoemission (ARPES) and optical measurements were performed on single crystal samples of LiCu2O2, an antiferromagnetic S=1/2 spin-chain compound. The ARPES spectra show several dispersive branches associated with hybrid copper-oxygen state ...

2006

Spin-orbit split two-dimensional electron gas with tunable Rashba and Fermi energy

Klaus Kern, Marco Grioni, Luca Moreschini

We demonstrate that it is possible to tune the Rashba energy, introduced by a strong spin-orbit splitting, and the Fermi energy in a two-dimensional electron gas by a controlled change of stoichiometry in an artificial surface alloy. In the BixPb1-x/Ag(111 ...

2008

High-energy photoemission in silver: resolving d and sp contributions in valence band spectra

Marco Grioni

We present high-resolution valence band and core level spectra of silver for photoelectron kinetic energies up to 8 keV. At these kinetic energies we estimate a surface contribution of less than 3%. Taking advantage of the favourable sp/d relative cross-se ...

Institute of Physics2005

Influence of the substrate on the spin-orbit splitting in surface alloys on (111) noble-metal surfaces

Klaus Kern, Marco Grioni, Luca Moreschini

We have studied by angle-resolved photoelectron spectroscopy the ordered XCu2 surface alloys formed by X=Sb and Bi on a Cu(111) substrate. We found clear analogies with the corresponding XAg2 alloys formed by the same elements on Ag(111). The electronic st ...

2009

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

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

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

Results and perspectives in hard X-ray photoemission spectroscopy (HAXPES) from solids

Marco Grioni

We report on the results obtained during the commissioning phase of the volume photoemission (VOLPE) project, now operational at ESRF. Test experiments were performed on noble metals and highly correlated systems, analyzing photoelectrons with kinetic ener ...

Elsevier2006

Assessing the atomic contribution to the Rashba spin-orbit splitting in surface alloys: Sb/Ag(111)

Klaus Kern, Marco Grioni, Luca Moreschini

We have studied the electronic structure of the Ag(111)(root 3x root 3)R30 degrees-Sb surface alloy by angle-resolved photoemission. We find two hybrid surface bands, similar to the isostructural Ag(111)-Bi interface. The spin-orbit coupling induced spin s ...

2009

Photoemission as a probe of coexisting and conflicting periodicities in low-dimensional solids

Helmuth Berger, Marco Grioni, Luca Perfetti

When two different periodic potentials are present at the same time in a solid, the electron wavefunctions must conform to the resulting overall periodicity. It is the case of the broken-symmetry phases which are often observed in low-dimensional systems. ...

Institute of Physics (IoP) and Deutsche Physikalische Gesellschaft2005

Structural and electronic properties of the Bi/Au(110)-1x4 surface

Harald Brune, Marco Grioni, Oleg Yazyev, François Patthey, Marina Pivetta, Alberto Crepaldi, Gabriel Albert Autes, Cédric Tournier-Colletta

We report on the structural and electronic properties of the Bi/Au(110)-1 x 4 surface, by combining scanning tunneling microscopy, angle-resolved photoemission spectroscopy, and first-principles calculations. The analysis of the precursor 1 x 8 moire struc ...

American Physical Society2013

Understanding mixed valent materials: Effects of dynamical core-hole screening in high-pressure x-ray spectroscopy

Marco Grioni

Changes in the electronic structure of Yb, a material whose valence is modified under pressure, are observed with remarkable detail in x-ray absorption and emission data measured between ambient conditions and 20 GPa. These changes are reproduced by a theo ...

2006

Band structure scenario for the giant spin-orbit splitting observed at the Bi/Si(111) interface

Marco Grioni, Emmanouil Frantzeskakis

The Bi/Si(111) (root 3 x root 3)R30 degrees trimer phase offers a prime example of a giant spin-orbit splitting of the electronic states at the interface with a semiconducting substrate. We have performed a detailed angle-resolved photoemission spectroscop ...

2010

Intermediate valence behaviour under pressure: how precisely can we probe it by means of resonant inelastic x-ray emission?

Marco Grioni

Rare earths and their compounds show many interesting physical phenomena caused by the complex electronic structure related to f electrons. External pressure can affect the hybridization between 5d band electrons and the more atomic-like 4f ones, giving ri ...

Institute of Physics2005

Nature of the Bad Metallic Behavior of Fe1.06Te Inferred from Its Evolution in the Magnetic State

Marco Grioni, Ping-Hui Lin

We investigate with angle-resolved photoelectron spectroscopy the changes of the Fermi surface and the main bands from the paramagnetic state to the antiferromagnetic (AFM) state occurring below 72 K in Fe1.06Te. The evolution is completely different from ...

Amer Physical Soc2013

Observation of Two Nondispersive Magnetic Excitations in NiO by Resonant Inelastic Soft-X-Ray Scattering

Helmuth Berger, Marco Grioni, Thorsten Schmitt, Xiaoqiang Wang

We present high resolution (Delta E=120 meV) resonant inelastic x-ray scattering data measured at the Ni L-3 edge (2p(3/2)-> 3d) on the paradigmatic antiferromagnetic oxide NiO. Spectra reveal clear signatures of magnetic excitations at similar to 95 and s ...

American Physical Society2009