Publications de Thorsten Schmitt

Momentum-resolved spin-conserving two-triplon bound state and continuum in a cuprate ladder

Henrik Moodysson Rønnow, Yi Tseng, Thorsten Schmitt, Vladimir N. Strocov

Studying multi-particle elementary excitations has provided unique access to understand collective many-body phenomena in correlated electronic materials, paving the way towards constructing microscopic models. In this work, we perform O K-edge resonant in ...

NATURE PORTFOLIO2023

Charge ordering in Ir dimers in the ground state of Ba5AlIr2O11

Oleg Yazyev, Xingye Lu, Vamshi Mohan Katukuri, Thorsten Schmitt, Vladimir N. Strocov

It has been well established experimentally that the interplay of electronic correlations and spin-orbit interactions in Ir4+ and Ir5+ oxides results in insulating J(eff) = 1/2 and J(eff) = 0 ground states, respectively. However, in compounds where the str ...

AMER PHYSICAL SOC2022

Crossover of high-energy spin fluctuations from collective triplons to localized magnetic excitations in Sr14-xCaxCu24O41 ladders

Henrik Moodysson Rønnow, Yi Tseng, Thorsten Schmitt

We studied the magnetic excitations in the quasi-one-dimensional (q-1D) ladder subsystem of Sr14-xCaxCu24O41 (SCCO) using Cu L-3-edge resonant inelastic X-ray scattering (RIXS). By comparing momentum-resolved RIXS spectra with high (x = 12.2) and without ( ...

NATURE PORTFOLIO2022

Resonant Inelastic X-Ray Scattering Study of Electron-Exciton Coupling in High-T-c Cuprates

Christophe Berthod, Fabrizio Carbone, Ivan Madan, Yi Tseng, Francesco Barantani, Thorsten Schmitt, Dirk Van der Marel

Explaining the mechanism of superconductivity in the high-T-c cuprates requires an understanding of what causes electrons to form Cooper pairs. Pairing can be mediated by phonons, the screened Coulomb force, spin or charge fluctuations, excitons, or by a c ...

American Physical Society2022

Weyl fermions, Fermi arcs, and minority-spin carriers in ferromagnetic CoS2

Samuel Thomas Stolz, Thorsten Schmitt, Timur Kim, Vladimir N. Strocov

Magnetic Weyl semimetals are a newly discovered class of topological materials that may serve as a platform for exotic phenomena, such as axion insulators or the quantum anomalous Hall effect. Here, we use angle-resolved photoelectron spectroscopy and ab i ...

2020

Resonant inelastic x-ray scattering study of Ca3Ru2O7

Qian Wang, Johan Juul Chang, Claudia Giuseppina Fatuzzo, Yi Tseng, Thorsten Schmitt

We present a combined oxygen K-edge x-ray absorption spectroscopy and resonant inelastic x-ray scattering (RIXS) study of the bilayer ruthenate Ca3Ru2O7. Our RIXS experiments on Ca3Ru2O7 were carried out on the overlapping planar and interplanar oxygen res ...

AMER PHYSICAL SOC2020

Electronic localization in CaVO3 films via bandwidth control

Xingye Lu, Thorsten Schmitt, Sophie Beck, Vladimir N. Strocov

Understanding and controlling the electronic structure of thin layers of quantum materials is a crucial first step towards designing heterostructures where new phases and phenomena, including the metal-insulator transition (MIT), emerge. Here, we demonstra ...

Springer2019

Strain-engineering Mott-insulating La2CuO4

Henrik Moodysson Rønnow, Johan Juul Chang, Yu-Pei Tseng, Noore Elahi Shaik, Yi Tseng, Thorsten Schmitt

The transition temperature T-c of unconventional superconductivity is often tunable. For a monolayer of FeSe, for example, the sweet spot is uniquely bound to titanium-oxide substrates. By contrast for La2-xSrxCuO4 thin films, such substrates are sub-optim ...

Nature Research2019

Probing multi-spinon excitations outside of the two-spinon continuum in the antiferromagnetic spin chain cuprate Sr2CuO3

Martin Mourigal, Henrik Moodysson Rønnow, Thorsten Schmitt

One-dimensional (1D) magnetic insulators have attracted significant interest as a platform for studying quasiparticle fractionalization, quantum criticality, and emergent phenomena. The spin-1/2 Heisenberg chain with antiferromagnetic nearest neighbour int ...

Nature Research2018

Kondo lattice excitation observed using resonant inelastic x-ray scattering at the YbM5 edge

Marco Grioni, Marco Guarise, Thorsten Schmitt

We present a study of the resonant inelastic scattering response of YbInCu4 excited at the tender YbM5 x-ray edge. In the high-temperature, paramagnetic phase, we observe a multiplet structure which can be understood at an ionic level. Upon cooling through ...

AMER PHYSICAL SOC2018

Direct observation of orbital hybridisation in a cuprate superconductor

Martin Mansson, Johan Juul Chang, Claudia Giuseppina Fatuzzo, Thorsten Schmitt

Nature Publishing Group2018

Dispersive magnetic and electronic excitations in iridate perovskites probed by oxygen K-edge resonant inelastic x-ray scattering

Henrik Moodysson Rønnow, Johan Juul Chang, Sara Fatale, Thorsten Schmitt

2018

Spin-Orbital Excitations in Ca2RuO4 Revealed by Resonant Inelastic X-Ray Scattering

Henrik Moodysson Rønnow, Johan Juul Chang, Claudia Giuseppina Fatuzzo, Yi Tseng, Thorsten Schmitt

American Physical Society2018

Electronic and magnetic excitations in the half-stuffed Cu-O planes of Ba2Cu3O4Cl2 measured by resonant inelastic x-ray scattering

Marco Grioni, Bruce Normand, Henrik Moodysson Rønnow, Peter Babkevich, Sara Fatale, Noore Elahi Shaik, Claudia Giuseppina Fatuzzo, Thorsten Schmitt

We use resonant inelastic x-ray scattering (RIXS) at the Cu L3 edge to measure the charge and spin excitations in the “half-stuffed” Cu-O planes of the cuprate antiferromagnet Ba2Cu3O4Cl2. The RIXS line shape reveals distinct contributions to the dd excita ...

2017

Sputtering-induced reemergence of the topological surface state in Bi2Se3

Stefan Peter Muff, Jan Hugo Dil, Thorsten Schmitt, Vladimir N. Strocov

We study the fate of the surface states of Bi2Se3 under disorder with strength larger than the bulk gap, caused by neon sputtering and nonmagnetic adsorbates. We find that neon sputtering introduces strong but dilute defects, which can be modeled by a unit ...

Amer Physical Soc2016

Three-dimensional momentum-resolved electronic structure of 1T-TiSe2: A combined soft-x-ray photoemission and density functional theory study

Helmuth Berger, Philipp Aebi, Elia Razzoli, Thorsten Schmitt

1T-TiSe2 is a quasi-two-dimensional transition metal dichalcogenide, which exhibits a charge density wave transition at a critical temperature of similar to 200 K as well as low-temperature superconductivity induced by pressure or intercalation. The electr ...

Amer Physical Soc2015

Probing two- and three-dimensional electrons in MgB2 with soft x-ray angle-resolved photoemission

Martin Mansson, Thorsten Schmitt

electronic band structure of MgB2 involves a unique combination of two-and three-dimensional (3D) electrons derived from the boron sigma and pi states, respectively. We have mapped out the sigma and pi bands over the complete Brillouin zone, including the ...

Amer Physical Soc2015

Magnons in tetragonal CuO

Marco Grioni, Frédéric Mila, Bastien Dalla Piazza, Henrik Moodysson Rønnow, Simon Karl Moser, Sara Fatale, Noore Elahi Shaik, Thorsten Schmitt

We investigate by resonant inelastic x-ray scattering the magnetic excitations in thin films of tetragonal CuO. We identify a spin wave excitation, dispersing on two cupratelike antiferromagnetic sublattices. Its energy at the boundary of the Brillouin zon ...

2015

Tuning electronic correlations in transition metal pnictides: Chemistry beyond the valence count

Philipp Aebi, Joël Mesot, Elia Razzoli, Thorsten Schmitt

The effects of electron-electron correlations on the low-energy electronic structure and their relationship with unconventional superconductivity are central aspects in the research on iron-based pnictide superconductors. Here we use soft x-ray angle-resol ...

Amer Physical Soc2015

Anisotropic softening of magnetic excitations along the nodal direction in superconducting cuprates

Helmuth Berger, Marco Grioni, Bastien Dalla Piazza, Henrik Moodysson Rønnow, Marco Guarise, Thorsten Schmitt

The high-T-c cuprate superconductors are close to antiferromagnetic order. Recent measurements of magnetic excitations have reported an intriguing similarity to the spin wavesmagnons- of the antiferromagnetic insulating parent compounds, suggesting that ma ...

Nature Publishing Group2014