Topological aspects of the quantum spin-Hall effect in graphene:Z2topological order and spin Chern number
نویسندگان
چکیده
منابع مشابه
Z2 topological order and the quantum spin Hall effect.
The quantum spin Hall (QSH) phase is a time reversal invariant electronic state with a bulk electronic band gap that supports the transport of charge and spin in gapless edge states. We show that this phase is associated with a novel Z2 topological invariant, which distinguishes it from an ordinary insulator. The Z2 classification, which is defined for time reversal invariant Hamiltonians, is a...
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We present a topological description of the quantum spin-Hall effect (QSHE) in a two-dimensional electron system on a honeycomb lattice with both intrinsic and Rashba spin-orbit couplings. We show that the topology of the band insulator can be characterized by a 2 x 2 matrix of first Chern integers. The nontrivial QSHE phase is identified by the nonzero diagonal matrix elements of the Chern num...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2007
ISSN: 1098-0121,1550-235X
DOI: 10.1103/physrevb.75.121403