Peculiarities of dynamics of Dirac fermions associated with zero-mass lines

Article

关键词: HGTE QUANTUM-WELLS;    TOPOLOGICAL INSULATORS;    TRANSITION;    GRAPHENE;    SOLITONS;    STATES;   

DOI  :  10.1103/PhysRevB.86.045419

来源: SCIE

【 摘 要 】

Zero-mass lines result in the appearance of linear dispersion modes for Dirac fermions. These modes play an important role in various physical systems. However, a Dirac fermion may not precisely follow a single zero-mass line, due to either tunneling between different lines or centrifugal forces. Being shifted from a zero-mass line the Dirac fermion acquires mass which can substantially influence its expected massless behavior. In the paper we calculate the energy gap caused by the tunneling between two zero-mass lines and show that its opening leads to the delocalization of linear dispersion modes. The adiabatic bending of a zero-mass line gives rise to geometric phases. These are the Berry phase, locally associated with a curvature, and a new phase, resulting from the mass square asymmetry in the vicinity of a zero-mass line.

【 授权许可】

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