Publications (38)
Electron-phonon coupling across the TMD/hBN van der Waals interface
G. Gatti, C. Berthod, J. Issing +18
Many-body interactions can couple electronic states in one layer with collective excitations in the adjacent layer, providing a route to tailor properties of heterostructures. Howe…
Spectroscopic view of ultrafast charge carrier dynamics in single- and bilayer transition metal dichalcogenide semiconductors
P. Majchrzak, K. Volckaert, A. G. Cabo +24
The quasiparticle spectra of atomically thin semiconducting transition metal dichalcogenides (TMDCs) and their response to an ultrafast optical excitation critically depend on inte…
Hydrogen Bonds in Excited State Proton Transfer
D. A. Horke, H. M. Watts, A. D. Smith +6
Hydrogen bonding interactions between biological chromophores and their surrounding protein and solvent environment significantly affect the photochemical pathways of the chromopho…
Momentum resolved spin dynamics of bulk and surface excited states in the topological insulator
C. Cacho, A. Crepaldi, M. Battiato +16
The prospective of optically inducing a spin polarized current for spintronic devices has generated a vast interest in the out-of-equilibrium electronic and spin structure of topol…
Evidence of reduced surface electron-phonon scattering in the conduction band of Bi_{2}Se_{3} by non-equilibrium ARPES
A. Crepaldi, F. Cilento, B. Ressel +11
The nature of the Dirac quasiparticles in topological insulators calls for a direct investigation of the electron-phonon scattering at the \emph{surface}. By comparing time-resolve…
Possible observation of parametrically amplified coherent phasons in K0.3MoO3 using time-resolved extreme-ultraviolet ARPES
H. Y. Liu, I. Gierz, J. C. Petersen +13
We use time- and angle-resolved photoemission spectroscopy (tr-ARPES) in the Extreme Ultraviolet (EUV) to measure the time- and momentum-dependent electronic structure of photo-exc…
Observation of Topological Superconductivity in a Stoichiometric Transition Metal Dichalcogenide 2M-WS2
Y. W. Li, H. J. Zheng, Y. Q. Fang +22
Topological superconductors (TSCs) are unconventional superconductors with bulk superconducting gap and in-gap Majorana states on the boundary that may be used as topological qubit…
Magnetic Weyl Semimetal Phase in a Kagome Crystal
D. F. Liu, A. J. Liang, E. K. Liu +16
Weyl semimetals are crystalline solids that host emergent relativistic Weyl fermions and have characteristic surface Fermi-arcs in their electronic structure. Weyl semimetals with…
Enhanced ultrafast relaxation rate in the Weyl semimetal phase of measured by time-and angle-resolved photoelectron spectroscopy
A. Crepaldi, G. Autès, G. Gatti +18
has recently been shown to realize in its low-temperature phase the type-II Weyl semimetal (WSM). We investigated by time- and angle- resolved photoelectron spect…
Discovery of an Antiferromagnetic Topological Nodal-line Kondo Semimetal
D. F. Liu, Y. F. Xu, H. Y. Hu +34
The symbiosis of strong interactions, flat bands, topology and symmetry has led to the discovery of exotic phases of matter, including fractional Chern insulators, correlated moirÃ…
Ab-initio simulations and measurements of the free-free opacity in Aluminum
P. Hollebon, O. Ciricosta, M. P. Desjarlais +6
The free-free opacity in dense systems is a property that both tests our fundamental understanding of correlated many-body systems, and is needed to understand the radiative proper…
Observation of a uniaxial strain-induced phase transition in the 2D topological semimetal IrTe
C. W. Nicholson, M. Rumo, A. Pulkkinen +12
Strain is ubiquitous in solid-state materials, but despite its fundamental importance and technological relevance, leveraging externally applied strain to gain control over materia…
Magnetic Excitations of a Half-Filled Tl-based Cuprate
I. BiaÅo, Q. Wang, J. Küspert +21
Strong electron correlations drive Mott insulator transitions. Yet, there exists no framework to classify Mott insulators by their degree of correlation. Cuprate superconductors, w…
The fate of quasiparticles at high-temperature
A. Hunter, S. Beck, E. Cappelli +17
We study the temperature evolution of quasiparticles in the correlated metal SrRuO. Our angle resolved photoemission data show that quasiparticles persist up to temperature…
Electronic reconstruction forming a -symmetric Dirac semimetal in CaRuO
M. Horio, Q. Wang, V. Granata +19
Electronic band structures in solids stem from a periodic potential reflecting the structure of either the crystal lattice or an electronic order. In the stoichiometric ruthenate C…
Observation of the Critical State to Multiple-Type Dirac Semimetal Phases in KMgBi
D. F. Liu, L. Y. W, C. C. Le +21
Dirac semimetals (DSMs) are classified into different phases based on the types of the Dirac fermions. Tuning the transition among different types of the Dirac fermions in one syst…
Orbital-selective charge-density wave in TaTe
R. Z. Xu, X. Du, J. S. Zhou +13
TaTe, a metallic charge-density wave (CDW) material discovered decades ago, has attracted renewed attention due to its rich interesting properties such as pressure-induced supe…
Revealing the role of electrons and phonons in the ultrafast recovery of charge density wave correlations in 1-TiSe
C. Monney, M. Puppin, C. W. Nicholson +8
Using time- and angle-resolved photoemission spectroscopy with selective near- and mid-infrared photon excitations, we investigate the femtosecond dynamics of the charge density wa…
Direct observation of the spin-orbit coupling effect in Magnetic Weyl semimetal Co3Sn2S2
D. F. Liu, E. K. Liu, Q. N. Xu +14
The spin-orbit coupling (SOC) lifts the band degeneracy that plays a vital role in the search for different topological states, such as topological insulators (TIs) and topological…
Tracking primary thermalization events in graphene with photoemission at extreme timescales
I. Gierz, F. Calegari, S. Aeschlimann +7
Direct and inverse Auger scattering are amongst the primary processes that mediate the thermalization of hot carriers in semiconductors. These two processes involve the annihilatio…
Orbital Complexity in Intrinsic Magnetic Topological Insulators MnBiTe and MnBiTe
R. C. Vidal, H. Bentmann, J. I. Facio +16
Using angle-resolved photoelectron spectroscopy (ARPES), we investigate the surface electronic structure of the magnetic van der Waals compounds MnBiTe and MnBiTe$_{10}…
Bonding states underpinning structural transitions in IrTe observed with micro-ARPES
C. W. Nicholson, M. D. Watson, A. Pulkkinen +6
Competing interactions in low-dimensional materials can produce nearly degenerate electronic and structural phases. We investigate the staircase of structural phase transitions in…
Topological Phase Transition in a Magnetic Weyl Semimetal
D. F. Liu, Q. N. Xu, E. K. Liu +15
Topological Weyl semimetals (TWSs) are exotic crystals possessing emergent relativistic Weyl fermions connected by unique surface Fermi-arcs (SFAs) in their electronic structures.…
Persistent gapless surface states in MnBi2Te4/Bi2Te3 superlattice antiferromagnetic topological insulator
L. X. Xu, Y. H. Mao, H. Y. Wang +21
Magnetic topological quantum materials (TQMs) provide a fertile ground for the emergence of fascinating topological magneto-electric effects. Recently, the discovery of intrinsic a…
Non-Fermi liquid quasiparticles in strain-tuned Sr2RuO4
A. Hunter, C. Putzke, F. B. Kugler +23
Interacting electrons can form metallic states beyond the Fermi liquid paradigm, a conceptual frontier of many-body physics mainly explored via bulk thermodynamics and transport. I…
Direct Observation of a Uniaxial Stress-driven Lifshitz Transition in SrRuO
V. Sunko, E. Abarca Morales, I. MarkoviÄ +11
Pressure represents a clean tuning parameter for traversing the complex phase diagrams of interacting electron systems and as such has proved of key importance in the study of quan…
Momentum-dependent scaling exponents of nodal self-energies measured in strange metal cuprates and modelled using semi-holography
S. Smit, E. Mauri, L. Bawden +13
The anomalous strange metal phase found in high- cuprates does not follow the conventional condensed-matter principles enshrined in the Fermi liquid and presents a great chall…
Spintronic superconductor in a bulk layered material with natural spin-valve structure
Shunsuke Sakuragi, S. Sasaki, R. Akashi +29
Multi-layered materials provide fascinating platforms to realize various functional properties, possibly leading to future electronic devices controlled by external fields. In part…
ARPES signatures of few-layer twistronic graphenes
J. E. Nunn, A. McEllistrim, A. Weston +7
Diverse emergent correlated electron phenomena have been observed in twisted graphene layers due to electronic interactions with the moiré superlattice potential. Many electronic…
Pseudogap Suppression by Competition with Superconductivity in La-Based Cuprates
J. Küspert, R. Cohn Wagner, C. Lin +23
We have carried out a comprehensive high-resolution angle-resolved photoemission spectroscopy (ARPES) study of the pseudogap interplay with superconductivity in La-based cuprates.…
Bulk and surface electronic structure of the dual-topology semimetal Pt2HgSe3
I. Cucchi, A. Marrazzo, E. Cappelli +12
We report high-resolution angle resolved photoemission measurements on single crystals of Pt2HgSe3 grown by high-pressure synthesis. Our data reveal a gapped Dirac nodal line whose…
Thermal hysteretic behavior and negative magnetoresistance in an unusual charge-density-wave material EuTe4
Q. Q. Zhang, Y. Shi, K. Y. Zhai +17
EuTe4 is a newly-discovered van der Waals material exhibiting a novel charge-density wave (CDW) with a large thermal hysteresis in the resistivity and CDW gap. In this work, we sys…
Topological Electronic Structure and Its Temperature Evolution in Antiferromagnetic Topological Insulator MnBi2Te4
Y. J. Chen, L. X. Xu, J. H. Li +17
Topological quantum materials coupled with magnetism can provide a platform for realizing rich exotic physical phenomena, including quantum anomalous Hall effect, axion electrodyna…
Antiferromagnetic topological insulator with selectively gapped Dirac cones
A. Honma, D. Takane, S. Souma +14
Antiferromagnetic (AF) topological materials offer a fertile ground to explore a variety of quantum phenomena such as axion magnetoelectric dynamics and chiral Majorana fermions. T…
Surface states and Rashba-type spin polarization in antiferromagnetic MnBiTe
R. C. Vidal, H. Bentmann, T. R. F. Peixoto +32
The layered van der Waals antiferromagnet MnBiTe has been predicted to combine the band ordering of archetypical topological insulators such as BiTe with the magnet…
Enhanced electron-phonon coupling in graphene with periodically distorted lattice
E. Pomarico, M. Mitrano, H. Bromberger +11
Electron-phonon coupling directly determines the stability of cooperative order in solids, including superconductivity, charge and spin density waves. Therefore, the ability to enh…
Revealing magnetism in the distorted kagome TiBi ( = Nd, Sm, Gd) via ARPES and XMCD
C. Lim, F. Ballester, A. Kar +19
Kagome materials are known for hosting emergent quantum phenomena driven by the interaction between different lattice, charge and spin orders. Here, we present a detailed angle res…
Distinctive Picosecond Spin Polarization Dynamics in Bulk Half-Metals
M. Battiato, J. Minar, W. Wang +7
Femtosecond laser excitations in half-metal (HM) compounds are theoretically predicted to induce an exotic picosecond spin dynamics. In particular, conversely to what is observed i…