▎ 摘　　要

Epsilon-near-zero (ENZ) mode, supported by a thin layer at the frequency where the real part of the dielectric constant vanishes, can significantly enhance the light-matter interaction at the deep subwavelength scale. However, ENZ modes exhibit the flat spectral dispersion which results in small group velocities and extremely short propagation lengths. Here, we propose a strong coupling system consisting of a polar dielectric GaAs nanolayer and a graphene sheet. In this system, ENZ mode and graphene plasmon (GP) mode can be simultaneously excited and they strongly couple with each other. The dispersions of the coupled ENZ-GP modes are characterized by an anti-crossing effect with a Rabi splitting energy on the order of 1/3 of the mode frequency. The figures of merit for the coupled modes, defined as the propagation length times the field confinement factor, are much larger than those of the uncoupled single mode. The hybridized ENZ-GP modes exhibit the combined features of long propagation length and strong optical field confinement, which can be used in the field of nanophotonic integration and communication.