Multi‐band and wide‐band electromagnetically induced transparency in graphene metasurface of composite structure

Abstract

The proposed graphene metasurface of composite structures of multi‐band and wide‐band transparency windows was investigated by the finite‐difference time‐domain method. The authors discussed a structure which consisted of graphene ribbons and TiO2–SiO2 layer which was sandwiched in between two lithium fluoride dielectric slabs. An electromagnetically induced transparency (EIT) window could be found and tuned gently by the width of lithium fluoride dielectric slabs. Furthermore, an improved structure of air groove in the graphene ribbon was designed. The result showed that a wide‐band EIT window was obtained and tuned by the width and thickness of air groove. The existing research shows that the graphene ribbon is bright mode and LiF slabs are dark mode. These results can find potential applications for many areas such as multi‐band wavelength slow‐light devices, active plasmon switching, infrared invisibility and optical sensing.

Electromagnetically induced transparency metamaterials: theories, designs and applications

“…Electromagnetically induced transparency (EIT) originates in a quantum physics system, where a narrow and sharp transparent window is formed due to the destructive interference among different excitation pathways within a broad absorption area [1][2][3][4][5]. This narrow transparent window is usually accompanied by abrupt phase variations and strong dispersions [6][7][8], which brings great convenience to its applications in realms of sensors [9][10][11][12][13], slow lights [14][15][16][17][18], absorbers [19][20][21][22][23], optical modulators [24,25], nonlinear enhancements [26,27], etc. However, the realizations of EIT effects in quantum systems need harsh experimental conditions, for instance, high strength laser sources and extremely low temperature [1,6,7], which seriously hamper the development of EIT-related technologies [28,29].…”

Robust Slow Light Enhancement Based on Flat Band States in the Continuum

“…Electromagnetic induced transparency (EIT), which is originally rooted in quantum physics system, has been widely used in the research of slow lights [48][49][50][51][52], sensors [53][54][55], absorbers [56][57][58], optical modulators [59,60], nonlinear enhancement [61,62], and other fields, due to its slow wave effect, strong dispersion, low absorption, and high-quality factor spectrum response. The analogue of EIT effect based on microwave metamaterials [52,[63][64][65], in particular, provides a new platform for the observation of slow wave effect, which not only is easy to adjust in structure, but also can visually reveal the strong dispersion effect caused by the EIT phenomenon.…”

Wideband tunable mid‐infrared cross‐polarisation converter using monolayered graphene‐based metasurface over a wide angle of incidence

“…By control of applied chemical potential and electrical grating, the plasmonic response of the graphene can be modulated in order to achieve tunability over a wide frequency of incidence [11,12]. Graphene layer has been incorporated in the unit cell of metasurface to generate wideband tunable applications toward absorber and filter [13,14]. Several issues persist on graphenebased metasurface and some of the reports have truly justified the capabilities of the graphene-based metasurface-based devices including resonators, filters, and absorbers [15].…”