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quanshengwu / wannier_tools

WannierTools: An open-source software package for novel topological materials. Full documentation:
http://www.wanniertools.org
GNU General Public License v3.0
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Left and right surfaces display different energy spectrum: Right surface show surface-states while left surface does not show. #79

Open abid-a opened 3 years ago

abid-a commented 3 years ago

Hi all, Using WannierTool, I calculated the surface-states for some 2D system. I observed that the left and right surfaces shows different spectrum. In particular the right surface shows robust surface-states while the left surfaces show insulating behavior. Now I am confused in the following points: (i) What you think, it is acceptable that both surfaces can have different spectrum? In other words, it is must to have similar behavior on both left and right surfaces? (ii) A bulk insulating system with topological protected surface states on only one surface while do not have surface-states on other surface, can be called a topological insulators (Z2 topological insulator)? I need your suggestions in this regard and possible hints

how to resolve this issue. Thank You

ElAlderson commented 1 year ago

Hello, This can be due to different terminations at the top and bottom surfaces ("_l" and "_r" respectively). Check your generated POSCAR-slab in VESTA. It would be same only if the terminations are same.