Excite Spoof Surface Plasmons with Tailored Wavefronts Using High-Efficiency Terahertz Metasurfaces.
Excite Spoof Surface Plasmons with Tailored Wavefronts Using High-Efficiency Terahertz Metasurfaces.
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使用高效太赫兹超表面通过定制波前激发欺骗表面等离子体
DOI：
10.1002/advs.202000982
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发表时间：
2020-10
期刊：
影响因子：
--
通讯作者：
Zhou L
中科院分区：
文献类型：
--
作者：
Wang Z;Li S;Zhang X;Feng X;Wang Q;Han J;He Q;Zhang W;Sun S;Zhou L
欺骗表面等离子体（SSP）在太赫兹（THz）近场光子学中发挥着至关重要的作用。然而，SSP的高效激发和波前工程仍然面临巨大的挑战，这阻碍了其在实践中的广泛应用。在这里，提出了一种方案，使用单个超紧凑设备同时有效地实现这两个目标。首先，研究表明，由高效 Pancharatnam-Berry (PB) 元原子构建的梯度元耦合器可以将圆偏振 (CP) 太赫兹光束转换为 SSP，绝对效率高达 60%。将抛物线相位分布编码到基于 PB 机制的元耦合器中，证明该装置可以将 CP 光束转换为具有聚焦或散焦波前的 SSP，具体取决于入射波的手性。最后，通过结合PB和共振相位机制，将两种不同的手性相关相位分布编码到元耦合器设计中，并证明所得元器件可以通过手性脱链双功能波前工程实现SSP激发。进行太赫兹近场实验来表征所有三种设备，与全波模拟非常一致。这些结果为实现在近场操作上集成不同功能的超紧凑器件铺平了道路，这些器件可以在不同频域中找到许多应用（例如光学传感、成像、片上光子学等）。通过单个超紧凑元设备可以对表面等离子体波前进行高效双功能操作。该元装置由具有几何相位和共振相位的元原子构成，对于具有不同自旋的照射光表现出不同的相位分布，从而产生独立的表面等离子体分布。这些发现可能会在集成光子学中找到许多应用，例如耦合片上光学器件和增强光与物质的相互作用。
Spoof surface plasmons (SSPs) play crucial roles in terahertz (THz) near‐field photonics. However, both high‐efficiency excitation and wavefront engineering of SSPs remain great challenges, which hinder their wide applications in practice. Here, a scheme is proposed to simultaneously achieve these two goals efficiently using a single ultracompact device. First, it is shown that a gradient meta‐coupler constructed by high‐efficiency Pancharatnam–Berry (PB) meta‐atoms can convert circularly polarized (CP) THz beams into SSPs with absolute efficiency up to 60%. Encoding a parabolic phase profile into the meta‐coupler based on the PB mechanism, it is demonstrated that the device can covert CP beams into SSPs with focusing or defocusing wavefronts, dictated by the chirality of the incident wave. Finally, two distinct chirality‐dependent phase distributions are encoded into the meta‐coupler design by combining the PB and resonance phase mechanisms, and it is demonstrated that the resulting meta‐device can achieve SSP excitations with chirality‐delinked bifunctional wavefront engineering. THz near‐field experiments are performed to characterize all three devices, in excellent agreement with full‐wave simulations. The results pave the road to realize ultracompact devices integrating different functionalities on near‐field manipulations, which can find many applications (e.g., optical sensing, imaging, on‐chip photonics, etc.) in different frequency domains. High‐efficiency bifunctional manipulations on surface‐plasmon wavefronts are enabled by a single ultracompact meta‐device. Constructed with meta‐atoms possessing both geometric and resonant phases, the meta‐device exhibits distinct phase profiles for impinging lights with different spins, thus generating independent surface‐plasmon profiles. These findings may find many applications in integration photonics, such as coupling on‐chip optical devices and enhancing light–matter interactions.
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影响因子：
56.9
作者：
Fang, N;Lee, H;Zhang, X
通讯作者：
Zhang, X
影响因子：
8.6
作者：
Lockyear, Matthew J.;Hibbins, Alastair P.;Sambles, J. Roy
通讯作者：
Sambles, J. Roy
影响因子：
8.6
作者：
Lalanne, P;Hugonin, JP;Rodier, JC
通讯作者：
Rodier, JC
高效手性调制欺骗表面等离子体元耦合器
影响因子：
4.6
作者：
Duan J;Guo H;Dong S;Cai T;Luo W;Liang Z;He Q;Zhou L;Sun S
通讯作者：
Sun S
DOI：
10.1049/pi-3.1953.0068
发表时间：
1953-01-01
期刊：
PROCEEDINGS OF THE INSTITUTION OF ELECTRICAL ENGINEERS-LONDON
影响因子：
--
作者：
BARLOW, HM;CULLEN, AL;KARBOWIAK, AE
通讯作者：
KARBOWIAK, AE