Topological insulator with time-reversal symmetry
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چکیده
It is impossible to have quantum Hall effect without breaking the time-reversal symmetry. xy xy. If we want xy to be invariant under , xy xy, xy must be zero. Q: Can we have other type of topological insulators, in the presence of -symmetry? By saying topological insulator, I mean an insulator with a protected metallic edge. By protected, I mean no matter what we do, we cannot turn the metallic edge into an insulating edge.
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