All-Dielectric Active Metasurface
Pin Chieh Wu1*
1Department of Photonics, National Cheng Kung University, Tainan, Taiwan
* Presenter:Pin Chieh Wu, email:pcwu@gs.ncku.edu.tw
Tunable metasurfaces enable active control of key constitutive properties of light at a sub-wavelength scale [1-3]. To achieve a widely tunable response at low input power and high speeds in active metasurface structures, electro-optical modulation of resonantly excited quantum well structures can enable strong light-matter interactions by couple of an optical field enhancement in an active material that can also undergo a large DC field modulation. In this talk, I will report an all-dielectric active metasurface platform based on electro-optically tunable III-V multiple-quantum-well (MQW) resonators [4]. In this work, we exploit the quantum-confined Stark effect in GaAs-based MQW resonators to actively control the optical response of the hybrid Mie-guided mode (Mie-GM) resonant metasurface phase and amplitude at near-infrared wavelengths. By applying a DC electric field across the all-dielectric resonators, we experimentally observe a relative reflectance modulation of ~270% accompanied with a continuous phase shift from 0° to 70°. In addition, we use our all-dielectric tunable metasurface to demonstrate a dynamically switchable diffraction grating and active beam steering.

References
1. A. M. Shaltout, V. M. Shalaev, and M. L. Brongersma, "Spatiotemporal light control with active metasurfaces," Science 364, eaat3100 (2019).
2. Q. He, S. Sun, and L. Zhou, "Tunable/reconfigurable metasurfaces: Physics and applications," Research 2019, 16 (2019).
3. Y. Huang, H. Xu, S. Sun, et. al., "Structured semiconductor interfaces: Active functionality on light manipulation," Proc. IEEE, 1-23 (2019).
4. P. C. Wu, R. A. Pala, G. Kafaie Shirmanesh, et. al., "Dynamic beam steering with all-dielectric electro-optic III–V multiple-quantum-well metasurfaces," Nat. Commun. 10, 3654 (2019).


Keywords: All-dielectric metasurface, Active control, Multiple-quantum-well