Orbitally induced string formation in the spin-orbital polarons

Abstract

We study the spectral function of a single hole doped into the (a,b) plane of the Mott insulator LaVO${}_3$, with antiferromagnetic (AF) spin order of S=1 spins accompanied by alternating orbital (AO) order of active $\{d_{yz},d_{zx}\}$ orbitals. Starting from the respective t-J model, with spin-orbital superexchange and effective three-site hopping terms, we derive the polaron Hamiltonian and show that a hole couples simultaneously to the collective excitations of the AF/AO phase, magnons and orbitons. Next, we solve this polaron problem using the self-consistent Born approximation and find a stable quasiparticle solution -- a spin-orbital polaron. We show that the spin-orbital polaron resembles the orbital polaron found in $e_g$ systems, as e.g. in K${}_2$CuF${}_4$ or (to some extent) in LaMnO${}_3$, and that the hole may be seen as confined in a string-like potential. However, the spins also play a crucial role in the formation of this polaron -- we explain how the orbital degrees of freedom: (i) confine the spin dynamics acting on the hole as the classical Ising spins, and (ii) generate the string potential which is of the joint spin-orbital character. Finally, we discuss the impact of the results presented here on the understanding of the phase diagrams of the lightly doped cubic vanadates.

18 pages, 10 figures; to appear in Physical Review B

References in corpus (15)

• Spin-orbital frustrations and anomalous metallic state in iron-pnictide superconductors
• Orbital fluctuations in the different phases of LaVO3 and YVO3
• Spin-Orbital Entanglement and Violation of the Goodenough-Kanamori Rules
• Evolution of Spin-Orbital-Lattice Coupling in the $R$VO${}_3$ Perovskites
• Theory of optical spectral weights in Mott insulators with orbital degrees of freedom
• Absence of Hole Confinement in Transition Metal Oxides with Orbital Degeneracy
• Orbital liquid in ferromagnetic manganites: The orbital Hubbard model for $e_g$ electrons
• Microscopic modelling of doped manganites
• Spectral properties of orbital polarons in Mott insulators
• Doping variation of anisotropic charge and orbital dynamics in Y1-xCaxVO3 : Comparison with La1-xSrxVO3
• One-dimensional orbital fluctuations and the exotic magnetic properties of YVO${}_3$
• Magnetic properties of spin-orbital polarons in lightly doped cobaltates
• One-electron self energies and spectral functions for the t-J model in the large-N limit
• Spin-polaron band structure and hole pockets in underdoped cuprates
• Double exchange model in cubic vanadates

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• Charge and orbital order in transition metal oxides
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• Green's function variational approach to orbital polarons in KCuF3
• Phase separation in the Edwards model
• Orbiton-magnon interplay in the spin-orbital polarons of KCuF3 and LaMnO3
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• Charge-density-wave formation in a half-filled fermion-boson transport model: A projective renormalization approach
• Unconventional superconductivity and interaction induced Fermi surface reconstruction in the two-dimensional Edwards model
• Multicomponent magneto-orbital order and magneto-orbitons in monolayer VCl3
• Altermagnetic polarons: the fate of alter magnetic band splittings at strong coupling
• Spectral properties of spin-orbital polarons as a fingerprint of orbital order
• A Green's function decoupling scheme for the Edwards fermion-boson model
• Dispersion of orbital excitations in 2D quantum antiferromagnets
• Orbital Rotations induced by Charges of Polarons and Defects in Doped Vanadates
• Spin-Orbital Liquid on a Triangular Lattice
• Charge-order melting in the one-dimensional Edwards model
• Quantum transport in an environment parametrized by dispersive bosons
• Orbital polaron in double exchange ferromagnets
• Magnetic polarons due to spin-length fluctuations in ${\mathbf{d}}^4$ spin-orbit Mott systems
• Spin-orbital polarons in electron doped copper oxides