Electronic Orbital Currents and Polarization in Mott Insulators

Abstract

The standard view is that at low energies Mott insulators exhibit only magnetic properties while charge degrees of freedom are frozen out as the electrons become localized by a strong Coulomb repulsion. We demonstrate that this is in general not true: for certain spin textures {\it spontaneous circular electric currents} or {\it nonuniform charge distribution} exist in the ground state of Mott insulators. In addition, low-energy ``magnetic'' states contribute comparably to the dielectric and magnetic functions ${\epsilon }_{ik}(\omega )$ and ${\mu }_{ik}(\omega )$ leading to interesting phenomena such as rotation the electric field polarization and resonances which may be common for both functions producing a negative refraction index in a window of frequencies.

References in corpus (6)

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• Role of the Dzyaloshinskii-Moriya interaction in multiferroic perovskites
• Multiferroics: different ways to combine magnetism and ferroelectricity
• Spin chirality on a two-dimensional frustrated lattice
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Cited by in corpus (4)

• Scalar spin chirality and quantum Hall effect on a triangular lattice
• Phase diagram of an anisotropic frustrated ferromagnetic spin-1/2 chain in a magnetic field: a density matrix renormalization group study
• Fermionic spin excitations in two and three-dimensional antiferromagnets
• Electron coherent and incoherent pairing instabilities in inhomogeneous bipartite and nonbipartite nanoclusters