No abstract

We present the tunable multiple plasmon-induced transparency (PIT) in the terahertz region by using a metamaterial made of two graphene bands and a graphene square ring. As the different modes of multiple PIT effects are independent of each other, the physical mechanism behind multiple PIT effects can be revealed by CMT theory. The PIT window changes significantly with the Fermi energy levels and structural parameters of graphene. The both three resonant frequencies increase linearly with the parameters and the Fermi energy changing, which can exhibit high sensitivities and figure of merit (FOM). Meanwhile, the amplitude modulation system can reach 99.63%, which can achieve excellent photoelectric switching. In addition, the group index can be as high as 2739. Therefore, the graphene-based metamaterial could be widely used in switches, modulators, excellent slow-light functional devices and filters in the terahertz region.

No abstract

Fano resonance is based on plasmonic metasurfaces and has many applications in all kinds of fields. In this paper, we propose an independently switchable double-layer raster structure based on graphene. Depending on the highly adjustable nature of graphene, the Fermi energy level can be adjusted to control the Fano resonance at different wavelengths. The equivalent resonator coupling mode method is used to simulate the Fano resonance, and the transmission spectrum fits well. Functional switch at different wavelengths can be achieved using Fano resonance technology. The simulation obtained a fantastic group refractive index of the designed structure, indicating that it there is a possibility to apply it in slow light. The effect of the environmental refractive index on sensing performance was studied and we found the structure has great potential in making high-sensitivity sensors. To sum up, it is hoped that this structure can make a great contribution to the manufacture of integrated optics.

We study on the joint training mode of optical engineering (OE) master in the ways of teaching, scientific research and practice cooperation. Our goal is to enhance the abilities and research level of OE graduate students by establishing the joint training cooperation with the domestic or foreign high level universities, the top research institutes and the famous enterprises, and to let more and more graduate students enter the high level universities and companies. In addition, we want to create the training quality evaluation index and evaluation system of the OE master students to evaluate this joint training mode.