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arXiv · 2302.12793

Tangent fermions: Dirac or Majorana fermions on a lattice without fermion doubling

C. W. J. Beenakker·A. Donis Vela·G. Lemut·M. J. Pacholski·J. Tworzydlo
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Abstract

I. Introduction II. Two-dimensional lattice fermions III. Methods to avoid fermion doubling (sine dispersion, sine plus cosine dispersion, staggered lattice dispersion, linear sawtooth dispersion, tangent dispersion) IV. Topologically protected Dirac cone V. Application: Klein tunneling (tangent fermions on a space-time lattice, wave packet propagation) VI. Application: Strong antilocalization (transfer matrix of tangent fermions, topological insulator versus graphene) VII. Application: Anomalous quantum Hall effect (gauge invariant tangent fermions, topologically protected zeroth Landau level) VIII. Application: Majorana metal (Dirac versus Majorana fermions, phase diagram) IX. Outlook

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C. W. J. Beenakker, A. Donis Vela, G. Lemut, M. J. Pacholski, J. Tworzydlo. 2023-02-24. Tangent fermions: Dirac or Majorana fermions on a lattice without fermion doubling. https://doi.org/10.1002/andp.202300081

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