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arXiv · 0710.3437

Electronic Structures of CaAlSi with Different Stacking AlSi Layers by First-Principles Calculations

S. Kuroiwa·A. Nakashima·S. Miyahara·N. Furukawa·J. Akimitsu
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Abstract

The full-potential linear augmented plane-wave calculations have been applied to investigate the systematic change of electronic structures in CaAlSi due to different stacking sequences of AlSi layers. The present ab-initio calculations have revealed that the multistacking, buckling and 60 degrees rotation of AlSi layer affect the electronic band structure in this system. In particular, such a structural perturbation gives rise to the disconnected and cylindrical Fermi surface along the M-L lines of the hexagonal Brillouin zone. This means that multistacked CaAlSi with the buckling AlSi layers increases degree of two-dimensional electronic characters, and it gives us qualitative understanding for the quite different upper critical field anisotropy between specimens with and without superstructure as reported previously.

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S. Kuroiwa, A. Nakashima, S. Miyahara, N. Furukawa, J. Akimitsu. 2007-10-18. Electronic Structures of CaAlSi with Different Stacking AlSi Layers by First-Principles Calculations. https://doi.org/10.1143/jpsj.76.113705

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