Floquet engineering of low-energy dispersions and dynamical localization in a periodically kicked three-band system

Article

关键词: TOPOLOGICAL INSULATOR;    ELECTRONIC-PROPERTIES;    DIFFUSION;    GRAPHENE;    ABSENCE;   

DOI  :  10.1103/PhysRevB.104.174308

来源: SCIE

【 摘 要 】

Although we know much about Floquet dynamics of pseudospin-1/2 systems, namely graphene, we here address the stroboscopic properties of a periodically kicked three-band fermionic system such as the alpha-T-3 lattice. This particular model provides an interpolation between graphene and dice lattice via the continuous tuning of the parameter alpha from 0 to 1. In the case of dice lattice (alpha = 1), we reveal that one can, in principle, engineer various types of low-energy dispersions around some specific points in the Brillouin zone by tuning the kicking parameter in the Hamiltonian along a particular direction. Our analytical analysis shows that one can experience different quasienergy dispersions, for example, the Dirac type, semi-Dirac type, gapless line, and/or absolute flat quasienergy bands, depending on the specific values of the kicking parameter. Moreover, we numerically study the dynamics of a wave packet in dice lattice. The quasienergy dispersion allows us to understand the instantaneous structure of wave packets at stroboscopic times. We find a situation where absolute flat quasienergy bands lead to a complete dynamical localization of the wave packet. Additionally, we calculate the quasienergy spectrum numerically for the alpha-T-3 lattice. A periodic kick in a perpendicular (planar) direction breaks (preserves) the particle-hole symmetry for 0 < alpha < 1. Furthermore, it is also revealed that the dynamical localization of a wave packet does not occur at any intermediate alpha not equal 0, 1.

【 授权许可】

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