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Geometric phases and Wannier functions of Bloch electrons in 1-dimension

Joydeep Bhattacharjee·Umesh V Waghmare
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Abstract

We present a formal expression for Wannier functions of composite bands of 1-D Bloch electrons in terms of parallel-transported Bloch functions and their non-Abelian geometric phases. Spatial decay properties of these Wannier functions are studied in the case of simple bands of 1-D model insulator and metal. Within first-principles density functional theory, we illustrate the formalism through the construction of Wannier functions of polyethylene and polyacetylene.

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Joydeep Bhattacharjee, Umesh V Waghmare. 2004-01-20. Geometric phases and Wannier functions of Bloch electrons in 1-dimension. https://doi.org/10.1103/physrevb.71.045106

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