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arXiv · 1301.6275

Orbital Magnetization as a Local Property

Raffaello Bianco·Raffaele Resta
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Abstract

The modern expressions for polarization $¶$ and orbital magnetization $\M$ are $\k$-space integrals. But a genuine bulk property should also be expressible in $\r$-space, as unambiguous function of the ground-state density matrix, "nearsighted" in insulators, independently of the boundary conditions---either periodic or open. While $¶$---owing to its "quantum" indeterminacy---is {\it not} a bulk property in this sense, $\M$ is. We provide its $\r$-space expression for any insulator, even with nonzero Chern invariant. Simulations on a model Hamiltonian validate our theory.

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Raffaello Bianco, Raffaele Resta. 2013-01-26. Orbital Magnetization as a Local Property. https://doi.org/10.1103/physrevlett.110.087202

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