Mechanically stretching has been an effective way to achieve widely tunable optical response in artificial nanostructures. However, the typical stretchable optical devices produce exactly the reverse effects for two orthogonal linear polarizations, significantly hindering their practical applications in many emerging systems. Herein, we demonstrate an approach for mechanically tunable all-dielectric metasurface with polarization-insensitivity and full-spectrum response in the visible range from 450 nm to 650 nm. By embedding a TiO2 metasurface in a polydimethylsiloxane (PDMS) substrate and stretching it in one direction, we find that the distinct reflection colors of two orthogonal linear polarizations can be tuned across the entire visible spectrum simultaneously. Encryption and display of information have also been realized with the same technique. The corresponding calculations show that the spectral responses of light with polarizations perpendicular and parallel to the strain are determined by two different mechanisms, i.e. the near-field mutual interaction and the grating effects. This research shall shed light on the stretchable and wearable photonics.

ACS Nano, Just Accepted Manuscript • DOI: 10.1021/acsnano.9b08228 • Publication Date (Web): 26 Dec 2019