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arXiv · 1508.00993

Orbital Magnetization in Insulators: Bulk vs. Surface

Raffaello Bianco·Raffaele Resta
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Abstract

The orbital magnetic moment of a finite piece of matter is expressed in terms of the one-body density matrix as a simple trace. We address a macroscopic system, insulating in the bulk, and we show that its orbital moment is the sum of a bulk term and a surface term, both extensive. The latter only occurs when the transverse conductivity is nonzero and owes to conducting surface states. Simulations on a model Hamiltonian validate our theory.

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Raffaello Bianco, Raffaele Resta. 2016-03-22. Orbital Magnetization in Insulators: Bulk vs. Surface. https://doi.org/10.1103/physrevb.93.174417

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