Artículos de revistas
Half-integer anomalous currents in 2D materials from a QFT viewpoint
Fecha
2022-12-01Registro en:
Scientific Reports, v. 12, n. 1, 2022.
2045-2322
10.1038/s41598-022-09483-4
2-s2.0-85127376080
Autor
KU Leuven Campus Kortrijk-Kulak
Ghent University
Universidade Estadual de Campinas (UNICAMP)
Universidad del Bio-Bio
Universidade Estadual Paulista (UNESP)
Institución
Resumen
Charge carriers in Dirac/Weyl semi-metals exhibit a relativistic-like behavior. In this work we propose a novel type of intrinsic half-integer Quantum Hall effect in 2D materials, thereby also offering a topological protection mechanism for the current. Its existence is rooted in the 2D parity anomaly, without any need for a perpendicular magnetic field. We conjecture that it may occur in disturbed honeycomb lattices where both spin degeneracy and time reversal symmetry are broken. These configurations harbor two distinct gap-opening mechanisms that, when occurring simultaneously, drive slightly different gaps in each valley, causing a net anomalous conductivity when the chemical potential is tuned to be between the distinct gaps. Some examples of promising material setups that fulfill the prerequisites of our proposal are also listed to motivate looking for the effect at the numerical and experimental level.