Publications (28)
Inequivalent routes across the Mott transition in V2O3 explored by X-ray absorption
F. Rodolakis, P. Hansmann, J. -P. Rueff +14
The changes in the electronic structure of V2O3 across the metal-insulator transition induced by temperature, doping and pressure are identified using high resolution x-ray absorpt…
Tree tensor-network real-time multiorbital impurity solver: Spin-orbit coupling and correlation functions in SrRuO
X. Cao, Y. Lu, P. Hansmann +1
We present a tree tensor-network impurity solver suited for general multiorbital systems. The network is constructed to efficiently capture the entanglement structure and symmetry…
Evolution of the electronic structure of a Mott system across its phase diagram: an X-ray absorption spectroscopy study of (V(1-x)Crx)2O3
F. Rodolakis, J. -P. Rueff, M. Sikora +12
V2O3 is an archetypal system for the study of correlation induced, Mott-Hubbard metal-insulator transitions. Despite decades of extensive investigations, the accurate description o…
A superlattice approach to doping infinite-layer nickelates
R. A. Ortiz, H. Menke, F. Misják +8
The recent observation of superconductivity in infinite-layer NdSrNiO thin films has attracted a lot of attention, since this compound is electronically and structu…
Electronic structure of nickelates: From two-dimensional heterostructures to three-dimensional bulk materials
P. Hansmann, A. Toschi, Xiaoping Yang +2
Reduced dimensionality and strong electronic correlations, which are among the most important ingredients for cupratelike high-Tc superconductivity, characterize also the physics o…
Pressure and alloying effects on the metal to insulator transition in NiS{2-x}Se{x} studied by infrared spectroscopy
A. Perucchi, C. Marini, M. Valentini +11
The metal to insulator transition in the charge transfer NiS{2-x}Se{x} compound has been investigated through infrared reflectivity. Measurements performed by applying pressure to…
A Unique Crystal Structure of CaRuO in the Current Stabilized Semi-Metallic State
J. Bertinshaw, N. Gurung, P. Jorba +13
The electric-current stabilized semi-metallic state in the quasi-two-dimensional Mott insulator CaRuO exhibits an exceptionally strong diamagnetism. Through a comprehensive…
Mott-Hubbard transition in V2O3 revisited
P. Hansmann, A. Toschi, G. Sangiovanni +4
The isostructural metal-insulator transition in Cr-doped V2O3 is the textbook example of a Mott-Hubbard transition between a paramagnetic metal and a paramagnetic insulator. We rev…
Distinct spin and orbital dynamics in SrRuO
H. Suzuki, L. Wang, J. Bertinshaw +13
The unconventional superconductor SrRuO has long served as a benchmark for theories of correlated-electron materials. The determination of the superconducting pairing mecha…
Dichotomy between large local and small ordered magnetic moment in Iron-based superconductors
P. Hansmann, R. Arita, A. Toschi +3
We study a four band model for iron-based superconductors within local density approximation + dynamical mean field theory (LDA+DMFT). This successfully reproduces the results of m…
A Microscopic View on the Mott transition in Chromium-doped V2O3
S. Lupi, L. Baldassarre, B. Mansart +18
V2O3 is the prototype system for the Mott transition, one of the most fundamental phenomena of electronic correlation. Temperature, doping or pressure induce a metal to insulator t…
Oxygen sublattice disorder and valence state modulation in infinite-layer nickelate superlattices
R. A. Ortiz, N. Enderlein, K. Fürsich +9
The family of infinite-layer nickelates promises important insights into the mechanism of unconventional superconductivity. Since superconductivity has so far only been observed in…
Control of the metal-insulator transition in NdNiO thin films through the interplay between structural and electronic properties
Y. E. Suyolcu, K. Fürsich, M. Hepting +10
Heteroepitaxy offers a new type of control mechanism for the crystal structure, the electronic correlations, and thus the functional properties of transition-metal oxides. Here, we…
Quantum dynamical screening of the local magnetic moment in Fe-based superconductors
A. Toschi, R. Arita, P. Hansmann +2
We have calculated the local magnetic susceptibility of one of the prototypical Fe-based superconductors (LaFeAsO) by means of the local density approximation + dynamical mean fiel…
Orbital characters of three-dimensional Fermi surfaces in Eu2-xSrxNiO4 as probed by soft-x-ray angle-resolved photoemission spectroscopy
M. Uchida, K. Ishizaka, P. Hansmann +13
The three-dimensional Fermi surface structure of hole-doped metallic layered nickelate Eu2-xSrxNiO4 (x=1.1), an important counterpart to the isostructural superconducting cuprate L…
A new benchmark of soft X-ray transition energies of Ne, CO, and SF: paving a pathway towards ppm accuracy
J. Stierhof, S. Kühn, M. Winter +24
A key requirement for the correct interpretation of high-resolution X-ray spectra is that transition energies are known with high accuracy and precision. We investigate the K-shell…
Natural-Orbital Impurity Solver and Projection Approach for Green's Function
Y. Lu, X. Cao, P. Hansmann +1
We extend a previously proposed rotation and truncation scheme to optimize quantum Anderson impurity calculations with exact diagonalization [PRB 90, 085102 (2014)] to density-matr…
Atomic and itinerant effects at the transition metal x-ray absorption K-pre-edge exemplified in the case of VO
P. Hansmann, M. W. Haverkort, A. Toschi +5
X-ray absorption spectroscopy is a well established tool for obtaining information about orbital and spin degrees of freedom in transition metal- and rare earth-compounds. For this…
Turning a nickelate Fermi surface into a cuprate-like one through heterostructuring
P. Hansmann, Xiaoping Yang, A. Toschi +3
Using the local density approximation and its combination with dynamical mean-field theory, we show that electronic correlations induce a single-sheet, cuprate-like Fermi surface f…
Bands, resonances, edge singularities and excitons in core level spectroscopy investigated within the dynamical mean field theory
M. W. Haverkort, G. Sangiovanni, P. Hansmann +3
Using a recently developed impurity solver we exemplify how dynamical mean field theory captures band excitations, resonances, edge singularities and excitons in core level x-ray a…
Effective crystal field and Fermi surface topology: a comparison of d- and dp-orbital models
N. Parragh, G. Sangiovanni, P. Hansmann +3
The effective crystal field in multi-orbital correlated materials can be either enhanced or reduced by electronic correlations with crucial consequences for the topology of the Fer…
Charge disproportionation and nano phase separation in SrNiO
H. Guo, Z. W. Li, C. F. Chang +16
We have successfully grown centimeter-sized layered SrNiO single crystals under high oxygen pressures of 120 bar by the floating zone technique. This enabled us to perform n…
Charge transfer energy in iridates: a hard x-ray photoelectron spectroscopy study
D. Takegami, D. Kasinathan, K. K. Wolff +20
We have investigated the electronic structure of iridates in the double perovskite crystal structure containing either Ir or Ir using hard x-ray photoelectron spectro…
Mechanism of charge transfer/disproportionation in LnCu3Fe4O12 (Ln: Lanthanides)
N. Rezaei, P. Hansmann, M. S. Bahramy +1
The Fe-Cu intersite charge transfer and Fe charge disproportionation are interesting phenomena observed in some LnCu3Fe4O12 (Ln: Lanthanides) compounds containing light and heavy L…
Exploring small energy scales with x-ray absorption and dichroism
C. Praetorius, M. Zinner, P. Hansmann +2
Soft x-ray linear and circular dichroism (XLD, XMCD) experiments at the Ce M edges are being used to determine the energy scales characterizing the Ce degrees of freed…
Pseudogap of metallic layered nickelate R2-xSrxNiO4 (R=Nd, Eu) crystals measured using angle-resolved photoemission spectroscopy
M. Uchida, K. Ishizaka, P. Hansmann +11
We have investigated charge dynamics and electronic structures for single crystals of metallic layered nickelates, R2-xSrxNiO4 (R=Nd, Eu), isostructural to La2-xSrxCuO4. Angle-reso…
Determining the crystal-field ground state in rare earth Heavy Fermion materials using soft-x-ray absorption spectroscopy
P. Hansmann, A. Severing, Z. Hu +10
We infer that soft-x-ray absorption spectroscopy is a versatile method for the determination of the crystal-field ground state symmetry of rare earth Heavy Fermion systems, complem…
Magnetic correlations in infinite-layer nickelates: an experimental and theoretical multi-method study
R. A. Ortiz, P. Puphal, M. Klett +12
We report a comprehensive study of magnetic correlations in LaNiO, a parent compound of the recently discovered family of infinite-layer (IL) nickelate superconductors, using…