Mechanically Tunable Dielectric Resonator Metasurfaces at Visible Frequencies

Abstract

Devices that manipulate light represent the future of information processing. Flat optics and structures with subwavelength periodic features (metasurfaces) provide compact and efficient solutions. The key bottleneck is efficiency, and replacing metallic resonators with dielectric resonators has been shown to significantly enhance performance. To extend the functionalities of dielectric metasurfaces to real-world optical applications, the ability to tune their properties becomes important. In this article, we present a mechanically tunable all-dielectric metasurface. This is composed of an array of dielectric resonators embedded in an elastomeric matrix. The optical response of the structure under a uniaxial strain is analyzed by mechanical−electromagnetic co-simulations. It is experimentally demonstrated that the metasurface exhibits remarkable resonance shifts. Analysis using a Lagrangian model reveals that strain modulates the near-field mutual interaction between resonant dielectric elements. The ability to control and alter inter-resonator coupling will position dielectric metasurfaces as functional elements of reconfigurable optical devices.

Metasurface Freeform Nanophotonics

“…While the experimentally measured change in the focal length is significantly smaller than the simple theoretical predictions in Fig. 4i, this change is still a significant change in focal length by a mechanically actuated metasurface-based tunable optical element 27, 31, 32 . In addition, we emphasize that the lens achieves most of its focal tuning range at a small range of physical displacement, in that we can tune the focal length by 2 mm using only around 30 μm of physical displacement.…”

All-dielectric ultrathin conformal metasurfaces: lensing and cloaking applications at 532 nm wavelength

“…In terms of the possible realization process, Si disks can be fabricated on a flat substrate through lithography and etching, followed by the spin-coating of the PDMS layer. Then, the PDMS layer with the disks embedded inside can be peeled off and transferred onto the desired platform2324. The low modulus and surface energy of PDMS allow conformal contact with the platform surface through Van der Waals interactions25.…”

Active Color Control in a Metasurface by Polarization Rotation

“…It implies that a whole new sample should be fabricated to produce different color or temporally varying color. As an alternative, adoption of mechanical transformation [17][18][19][20][21], chemical transition [22][23][24], phase change material [25][26][27][28] and electrochromic polymer [29] provide dynamic color printing. Nevertheless, dynamic color printing can be realized in a far simpler system by polarization control without involving any external stimuli [30][31][32].…”