Temperature-Driven Gapless Topological Insulator.

Phys Rev Lett

CeFEMA, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal.

Published: March 2019

We investigate the phase diagram of the Haldane-Falicov-Kimball model-a model combining topology, interactions, and spontaneous disorder at finite temperatures. Using an unbiased numerical method, we map out the phase diagram on the interaction-temperature plane. Along with known phases, we unveil an insulating charge ordered state with gapless excitations and a temperature-driven gapless topological insulating phase. Intrinsic-temperature-generated-disorder is the key ingredient explaining the unexpected behavior. Our findings support the possibility of having temperature-driven topological transitions into gapped and gapless topological insulating phases in mass unbalanced systems with two fermionic species.

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http://dx.doi.org/10.1103/PhysRevLett.122.126601DOI Listing

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