Landau subband wave functions and chirality manifestation in rhombohedral graphite

Recently, rhombohedral graphite has been known to have a three-dimensional Dirac cone structure composed of tilted anisotropic Dirac cones, as a result of the perturbative interlayer electron hoppings. The corresponding Landau subbands have weak energy dispersions, a characteristic indicating the possible occurrence of a three-dimensional quantum Hall effect in weak magnetic fields. Since the robust zero-mode Landau subband should be topologically protected by the chirality of the Dirac fermions, here we investigate the chirality for rhombohedral graphite with regard to the Dirac cone tilt and anisotropy, for which there could exist phases mixing in the Landau subband wave functions. Both a perturbation analysis and an exact diagonalization are performed for showing the effects of the interlayer hoppings on the phases mixing. In the results the perturbations due to the interlayer hoppings are not resolvable. Rhombohedral graphite turns out to have the same chiral nature as monolayer graphene. The realizability of the three-dimensional quantum Hall effect in rhombohedral graphite is thus further supported by the manifestation of chiralities.