Wang Hang, Ling Fang, Zhang Bin
Opt Express. 2020 Nov 23;28(24):36316-36326. doi: 10.1364/OE.405885.
Metasurfaces provide an extraordinary way to control electromagnetic waves by abrupt change of optical properties within an optically thin interface. In this paper, by introducing vanadium dioxide (VO) into the metasurface, efficient tunable terahertz phase modulation is designed to realize independent control of linearly and circularly polarized terahertz waves. The working resonator of the metasurface can be adjustable by controlling the temperature of VO, resulting in the tunable function between resonant phase for linearly polarized waves and Pancharatnam-Berry phase for circularly polarized waves. As a proof of concept, two metasurfaces are designed for integrating two distinct functionalities in one structure, i.e. 1-bit metasurface switched between the abnormal THz deflector and the THz scatter and 3-bit metasurface switched between the vortex THz transmitter and the THz focusing mirror. The proposed tunable resonator structure provides a flexible way for extending the functionality of metadevice, which has a great potential value in integrated optics and wearable optics.
超表面提供了一种非凡的方式，可通过光学薄界面内光学特性的突然变化来控制电磁波。在本文中，通过将二氧化钒（VO）引入超表面，设计了高效的可调谐太赫兹相位调制，以实现对线性和圆偏振太赫兹波的独立控制。超表面的工作谐振器可通过控制VO的温度进行调节，从而实现线性偏振波的谐振相位与圆偏振波的潘查拉特纳姆-贝里相位之间的可调功能。作为概念验证，设计了两种超表面，用于在一个结构中集成两种不同的功能，即1位超表面在异常太赫兹偏转器和太赫兹散射体之间切换，以及3位超表面在涡旋太赫兹发射器和太赫兹聚焦镜之间切换。所提出的可调谐谐振器结构为扩展超器件的功能提供了一种灵活的方式，在集成光学和可穿戴光学中具有巨大的潜在价值。
