Natalia B. Perkins

Importance of anisotropic exchange interactions in honeycomb iridates: Minimal model for zigzag antiferromagnetic order in Na2 IrO3

In this work, we investigate the microscopic nature of the magnetism in honeycomb iridium-based systems by performing a systematic study of how the effective magnetic interactions in these compounds depend on various electronic microscopic parameters. We show that the minimal model describing the magnetism in A

Spin-1 effective Hamiltonian with three degenerate orbitals: An application to the case of V2O3

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Structural distortion-induced magnetoelastic locking in Sr(2)IrO(4) revealed through nonlinear optical harmonic generation.

IrO

Phase diagram and quantum order by disorder in the kitaev K1 - K2 honeycomb magnet

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Raman Scattering Signatures of Kitaev Spin Liquids in A2IrO3 Iridates with A = Na or Li

includes both isotropic and anisotropic Kitaev-type spin-exchange interactions between nearest and next-nearest neighbor Ir ions, and that the magnitude of the Kitaev interaction between next-nearest neighbor Ir magnetic moments is comparable with nearest neighbor interactions. We also find that, while the Heisenberg and the Kitaev interactions between nearest neighbors are correspondingly antiferro- and ferromagnetic, they both change sign for the next-nearest neighbors. Using classical Monte Carlo simulations we examine the magnetic phase diagram of the derived super-exchange model. Zigzag-type antiferromagnetic order is found to occupy a large part of the phase diagram of the model and, for ferromagnetic next-nearest neighbor Heisenberg interaction relevant for Na

Critical properties of the Kitaev-Heisenberg model.

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Orbital order in vanadium spinels

IrO

Valence-bond crystal in a pyrochlore antiferromagnet with orbital degeneracy.

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Classical spin liquid instability driven by off-diagonal exchange in strong spin-orbit magnets

, it can be stabilized even in the absence of third nearest neighbor coupling. Our results suggest that a natural physical origin of the zigzag phase experimentally observed in Na

Magnetism in parent iron chalcogenides: quantum fluctuations select plaquette order.

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