An actively ultrafast tunable giant slow-light effect in ultrathin nonlinear metasurfaces

作者：Lu Cuicui; Hu Xiaoyong^*; Shi Kebin; Hu Qin; Zhu Rui; Yang Hong; Gong Qihuang

来源：Light: Science and Applications , 2015, 4(6): e302.

DOI：10.1038/lsa.2015.75

• graphene
• metamaterial-induced transparency
• metasurfaces
• slow light effect
• Zno nanoparticles

A slow-light effect based on metamaterial-induced transparency (MIT) possesses great practical applications for integrated photonic devices. However, to date, only very weak slow-light effects have been obtained in metamaterials because of the intrinsic loss of metal. Moreover, no active control of slow-light has been achieved in metamaterials. Here, we report the realization of a giant slow-light effect on an ultrathin metasurface that consists of periodic arrays of gold nanoprism dimers with a thickness of 40 nm sandwiched between a multilayer-graphene micro-sheet/zinc oxide nanoparticle layer and a monolayer graphene/polycrystalline indium tin oxide layer. The strong field confinement of the plasmonic modes associated with the MIT ensures a tremendous reduction in the group velocity around the transparency A group index of more than 4 x 10(3) is achieved, which is one order of magnitude greater than that of previous reports. A large tunable wavelength range of 120 nm is achieved around the center of the transparency window when the pump light intensity is only 1.5 kW cm(-2). The response time is as fast as 42.3 ps. These results demonstrate the potential for the realization of various functional integrated photonic devices based on metasurfaces, such as all-optical buffers and all-optical switches.

• 出版日期2015-6
• 单位北京大学