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arXiv · 1904.11394

Geometric orbital magnetization in adiabatic processes

Luka Trifunovic·Seishiro Ono·Haruki Watanabe
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Abstract

We consider periodic adiabatic processes of gapped many-body spinless electrons. We find an additional contribution to the orbital magnetization due to the adiabatic time evolution, dubbed \textit{geometric} orbital magnetization, which can be expressed as derivative of the many-body Berry phase with respect to an external magnetic field. For two-dimensional band insulators, we show that the geometric orbital magnetization generally consists of two pieces, the topological piece that is expressed as third Chern-Simons form in $(t,k_x,k_y)$ space, and the non-topological piece that depends on Bloch states and energies of both occupied and unoccupied bands.

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Luka Trifunovic, Seishiro Ono, Haruki Watanabe. 2019-08-09. Geometric orbital magnetization in adiabatic processes. https://doi.org/10.1103/physrevb.100.054408

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