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Complex band structure with ultrasoft pseudopotentials: fcc Ni and Ni nanowire

A. Smogunov·A. Dal Corso·E. Tosatti
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Abstract

We generalize to magnetic transition metals the approach proposed by Choi and Ihm for calculating the complex band structure of periodic systems, a key ingredient for future calculations of conductivity of an open quantum system within the Landauer-Buttiker theory. The method is implemented with ultrasoft pseudopotentials and plane wave basis set in a DFT-LSDA ab-initio scheme. As a first example, we present the complex band structure of bulk fcc Ni (which constitutes the tips of a Ni nanocontact) and monatomic Ni wire (the junction between two tips). Based on our results, we anticipate some features of the spin-dependent conductance in a Ni nanocontact.

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A. Smogunov, A. Dal Corso, E. Tosatti. 2003-02-05. Complex band structure with ultrasoft pseudopotentials: fcc Ni and Ni nanowire. https://doi.org/10.1016/s0039-6028(03)00453-9

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