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arXiv · 1403.6883

Compressed Wannier modes found from an $L_1$ regularized energy functional

Farzin Barekat·Ke Yin·Russel E. Caflisch·Stanley J. Osher·Rongjie Lai·Vidvuds Ozolins
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Abstract

We propose a method for calculating Wannier functions of periodic solids directly from a modified variational principle for the energy, subject to the requirement that the Wannier functions are orthogonal to all their translations ("shift-orthogonality"). Localization is achieved by adding an $L_1$ regularization term to the energy functional. This approach results in "compressed" Wannier modes with compact support, where one parameter $μ$ controls the trade-off between the accuracy of the total energy and the size of the support of the Wannier modes. Efficient algorithms for shift-orthogonalization and solution of the variational minimization problem are demonstrated.

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Farzin Barekat, Ke Yin, Russel E. Caflisch, Stanley J. Osher, Rongjie Lai, Vidvuds Ozolins. 2014-03-26. Compressed Wannier modes found from an $L_1$ regularized energy functional. https://arxiv.org/abs/1403.6883

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