Magnetic breakdown spectrum of a Kramers–Weyl semimetal

Abstract

We calculate the Landau levels of a Kramers–Weyl semimetal thin slab in a perpendicular magnetic field B . The coupling of Fermi arcs on opposite surfaces broadens the Landau levels with a band width that oscillates periodically in 1/ B . We interpret the spectrum in terms of a one-dimensional superlattice induced by magnetic breakdown at Weyl points. The band width oscillations may be observed as 1/ B -periodic magnetoconductance oscillations, at weaker fields and higher temperatures than the Shubnikov–de Haas oscillations due to Landau level quantization. No such spectrum appears in a generic Weyl semimetal, the Kramers degeneracy at time-reversally invariant momenta is essential.

Keywords

• Landau levels
• Fermi arcs
• Kramers degeneracy
• magnetic oscillations