Tian Jingyi, Li Qiang, Lu Jun, Qiu Min
Opt Express. 2018 Sep 3;26(18):23918-23925. doi: 10.1364/OE.26.023918.
Dielectric nanoantenna-based metasurfaces have attracted wide attention for their outstanding performance in light manipulation with low loss and full phase coverage enabled by multipolar resonances. To make the metasurfaces actively tunable, we adopt a kind of phase-changing material GeSbTe to construct non-volatile, switchable antenna-based metasurfaces in the mid-infrared spectrum region. Our design of the metasurface can realize switching between electric and magnetic dipole resonances across a broad spectrum region through crystalline-amorphous phase transitions under fixed design. Moreover, the transmission switching contrast between different phases can be up to 30dB (-30dB), due to the shift of multipolar resonances. This reconfigurable antenna-based metasurface will pave the way for ultimate design of light modulators, deflectors, holograms and so on for future optical communication networks.
基于介电纳米天线的超表面因其在光操纵方面的出色性能而备受关注,该性能通过多极共振实现低损耗和全相位覆盖。为了使超表面能够主动调谐,我们采用一种相变材料GeSbTe在中红外光谱区域构建基于天线的非易失性、可切换超表面。我们的超表面设计可以在固定设计下通过晶态-非晶态相变在宽光谱区域实现电偶极子和磁偶极子共振之间的切换。此外,由于多极共振的移动,不同相之间的传输切换对比度可达30dB(-30dB)。这种基于可重构天线的超表面将为未来光通信网络中光调制器、偏转器、全息图等的最终设计铺平道路。