179 citations · 2.1k across the 56 of their papers we have counts for
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Orbital Rotations induced by Charges of Polarons and Defects in Doped Vanadates
Peter Horsch, Andrzej M. Oleś, Adolfo Avella
We explore the competiton of doped holes and defects that leads to the loss of orbital order in vanadate perovskites. In compounds such as LaCaVO spin…
Defect-induced orbital polarization and collapse of orbital order in doped vanadium perovskites
Adolfo Avella, Andrzej M. Oleś, Peter Horsch
We explore mechanisms of orbital order decay in doped Mott insulators (Sr,Ca)VO (Pr,Y,La) caused by charged (Sr,Ca) defects. Our unrestricted Hartree-Fock an…
Fingerprints of spin-orbital polarons and of their disorder in the photoemission spectra of doped Mott insulators with orbital degeneracy
Adolfo Avella, Andrzej M. Oleś, Peter Horsch
We explore the effects of disordered charged defects on the electronic excitations observed in the photoemission spectra of doped transition metal oxides in the Mott insulating reg…
Defects, disorder and strong electron correlations in orbital degenerate, doped Mott insulators
Adolfo Avella, Andrzej M. Oleś, Peter Horsch
We elucidate the effects of defect disorder and - interaction on the spectral density of the defect states emerging in the Mott-Hubbard gap of doped transition-metal oxides,…
Quantum entanglement in the one-dimensional spin-orbital SU(2) model
Wen-Long You, Peter Horsch, Andrzej M. Oleś
We investigate the phase diagram and the spin-orbital entanglement of a one-dimensional SU(2) model with SU(2) spin exchange and anisotropic orbital exchange int…
Entanglement Driven Phase Transitions in Spin-Orbital Models
Wen-Long You, Andrzej M. Oleś, Peter Horsch
To demonstrate the role played by the von Neumann entropy spectra in quantum phase transitions we investigate the one-dimensional anisotropic SU(2) spin-orbital model…
Exact treatment of magnetism-driven ferroelectricity in the one-dimensional compass model
Wen-Long You, Guang-Hua Liu, Peter Horsch +1
We consider a class of one-dimensional compass models with antisymmetric Dzyaloshinskii-Moriya exchange interaction in an external magnetic field. Based on the exact solution deriv…
Quantum phase transitions in exactly solvable one-dimensional compass models
Wen-Long You, Peter Horsch, Andrzej M. Oleś
We present an exact solution for a class of one-dimensional compass models which stand for interacting orbital degrees of freedom in a Mott insulator. By employing the Jordan-Wigne…
Hole propagation in the Kitaev-Heisenberg model: From quasiparticles in quantum Neel states to non-Fermi liquid in the Kitaev phase
Fabien Trousselet, Peter Horsch, Andrzej M. Oles +1
We explore with exact diagonalization the propagation of a single hole in four magnetic phases of the t-J-like Kitaev-Heisenberg model on a honeycomb lattice: the Neel antiferromag…
Hidden Quasiparticles and Incoherent Photoemission Spectra in Na2IrO3
Fabien Trousselet, Mona Berciu, Andrzej M. Oles +1
We study two Heisenberg-Kitaev t-J-like models on a honeycomb lattice, focusing on the zigzag magnetic phase of NaIrO, and investigate hole motion by exact diagonalization…
Defect states and excitations in a Mott insulator with orbital degrees of freedom: Mott-Hubbard gap versus optical and transport gaps in doped systems
Adolfo Avella, Peter Horsch, Andrzej M. Oleś
We address the role played by charged defects in doped Mott insulators with active orbital degrees of freedom. It is observed that defects feature a rather complex and rich physics…
Defect states and spin-orbital physics in doped vanadates Y1-xCaxVO3
Peter Horsch, Andrzej M. Oles
We present a model for typical charged defects in weakly doped Y1-xCaxVO3 perovskites and study how they influence the magnetic and orbital order. Starting from a multiband Hubbard…
Von Neumann Entropy Spectra and Entangled Excitations in Spin-Orbital Models
Wen-Long You, Andrzej M. Oleś, Peter Horsch
We consider the low-energy excitations of one-dimensional spin-orbital models which consist of spin waves, orbital waves, and joint spin-orbital excitations. Among the latter we id…
Effects of spin vacancies on magnetic properties of the Kitaev-Heisenberg model
Fabien Trousselet, Giniyat Khaliullin, Peter Horsch
We study the ground state properties of the Kitaev-Heisenberg model in a magnetic field and explore the evolution of spin correlations in the presence of non-magnetic vacancies. By…
Spin exchange dominated by charge fluctuations of the Wigner lattice in the newly synthesized chain cuprate Na5Cu3O6
N. Zafar Ali, J. Sirker, J. Nuss +2
Na5Cu3O6, a new member of one dimensional charge ordered chain cuprates, was synthesized via the azide/nitrate route by reacting NaN3, NaNO3 and CuO. According to single crystal X-…
Magnetic excitations in one-dimensional spin-orbital models
A. Herzog, A. M. Oles, P. Horsch +1
We study the dynamics and thermodynamics of one-dimensional spin-orbital models relevant for transition metal oxides. We show that collective spin, orbital, and combined spin-orbit…
Orbital fluctuations in the VO perovskites
Andrzej M. Oleś, Peter Horsch
The properties of Mott insulators with orbital degrees of freedom are described by spin-orbital superexchange models, which provide a theoretical framework for understanding their…
Compass-Heisenberg Model on the Square Lattice : Spin Order and Excitations
Fabien Trousselet, Andrzej M. Oles, Peter Horsch
We explore the physics of the anisotropic compass model under the influence of perturbing Heisenberg interactions and present the phase diagram with multiple quantum phase transiti…
Spin-wave theory for dimerized ferromagnetic chains
Alexander Herzog, Peter Horsch, Andrzej M. Oles +1
We describe a Peierls dimerization which occurs in ferromagnetic spin chains at finite temperature, within the modified spin-wave theory. Usual spin-wave theory is modified by intr…
Orbitally induced string formation in the spin-orbital polarons
Krzysztof Wohlfeld, Andrzej M. Oles, Peter Horsch
We study the spectral function of a single hole doped into the (a,b) plane of the Mott insulator LaVO, with antiferromagnetic (AF) spin order of S=1 spins accompanied by altern…
Reiter's polaron wavefunction applied to a orbital t-J model
Krzysztof Wohlfeld, Andrzej M. Oles, Maria Daghofer +1
Using the self-consistent Born approximation we calculate Reiter's wavefunction for a single hole introduced into the undoped and orbitally ordered ground state of the t-J model wi…
Spectral properties of orbital polarons in Mott insulators
Krzysztof Wohlfeld, Maria Daghofer, Andrzej M. Oles +1
We address the spectral properties of Mott insulators with orbital degrees of freedom, and investigate cases where the orbital symmetry leads to Ising-like superexchange in the orb…
Thermally activated Peierls dimerization in ferromagnetic spin chains
J. Sirker, A. Herzog, A. M. Oles +1
We demonstrate that a Peierls dimerization can occur in ferromagnetic spin chains activated by thermal fluctuations. The dimer order parameter and entanglement measures are studied…
Evolution of Spin-Orbital-Lattice Coupling in the VO Perovskites
Peter Horsch, Andrzej M. Oles', Louis Felix Feiner +1
We introduce a microscopic model which unravels the physical mechanisms responsible for the observed phase diagram of the VO perovskites. It reveals a nontrivial interplay b…