Diabolical touching point in the magnetic energy levels of topological nodal-line metals

Article

关键词: QUANTUM OSCILLATIONS;    BLOCH ELECTRONS;    COUPLED ORBITS;    ABSORPTION;    BREAKDOWN;    PHASE;    SUSCEPTIBILITY;    QUANTIZATION;    INTERSECTION;    DYNAMICS;   

DOI  :  10.1103/PhysRevB.105.045141

来源: SCIE

【 摘 要 】

For three-dimensional metals, Landau levels disperse as a function of the magnetic field and the momentum wave number parallel to the field. In this two-dimensional parameter space, it is shown that two conically dispersing Landau levels can touch at a diabolical point-a Landau-Dirac point. The conditions giving rise to Landau-Dirac points are shown to be magnetic breakdown (field-driven quantum tunneling) and certain crystallographic spacetime symmetry. Both conditions are realizable in topological nodal-line metals, as we exemplify with the material candidates CaX3 (X = As, P). The experimental fingerprints of a Landau-Dirac point include (a) anomalous batman-like peaks in the magnetoresistance, (b) circular Landau-Fermi surfaces revealed by angle-dependent ultrasonic attenuation, and (c) the tunability of the frequency onset of optical absorption to zero.

【 授权许可】

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