Nieh-Yan anomaly: Torsional Landau levels, central charge, and anomalous thermal Hall effect

  title={Nieh-Yan anomaly: Torsional Landau levels, central charge, and anomalous thermal Hall effect},
  author={Ze-Min Huang and Bolin Han and Michael A. Stone},
  journal={Physical Review B},
The Nieh-Yan anomaly is the anomalous breakdown of the chiral U(1) symmetry caused by the interaction between torsion and fermions. We study this anomaly from the point of view of torsional Landau levels. It was found that the torsional Landau levels are gapless, while their contributions to the chiral anomaly are canceled, except those from the lowest torsional Landau levels. Hence, the dimension is effectively reduced from (3+1)-dimensional to (1+1)-dimensional. We further show that the… 

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