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arXiv · 2110.05364

Local vs non-local correlation effects in interacting quantum spin Hall insulators

Lorenzo Crippa·Adriano Amaricci·Severino Adler·Giorgio Sangiovanni·Massimo Capone
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Abstract

The impact of Coulomb interaction on the electronic properties of a quantum spin-Hall insulator is studied using quantum cluster methods, disentangling local from non-local effects. We identify different regimes, according to the value of the bare mass term, characterized by drastically different self-energy contributions. For small mass, non-local correlations start to be important and eventually dominate over local ones when getting close enough to the zero-mass semi-metallic line. For intermediate and large mass, local correlation effects outweigh non-local corrections, leading to a first-order topological phase transition, in agreement with previous predictions.

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Lorenzo Crippa, Adriano Amaricci, Severino Adler, Giorgio Sangiovanni, Massimo Capone. 2021-10-11. Local vs non-local correlation effects in interacting quantum spin Hall insulators. https://doi.org/10.1103/physrevb.104.235117

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