Soft‐Matter‐Based Hybrid and Active Metamaterials

Abstract

Figure 6. a) Plasmonic shallow nanowells infiltrated with high birefringence LC showing display potential. b) LC plasmonic MS color tag. c) LC MS enabling electrically tunable holograms switching using circular polarization. d) Polarization-sensitive encryption using polymer-dispersed LC. a) Adapted with permission. [80]

Reversible Microscale Assembly of Nanoparticles Driven by the Phase Transition of a Thermotropic Liquid Crystal

“…As a model platform, this materials system provides insights into the control over the size and spatial arrangement of hierarchical microstructures from nanoscale building blocks formed by liquid–liquid phase separation . The observation of controlled and phase transition-driven reversible assembly of gold NPs takes inspiration from other forms of stimuli-directed self-assembly, where the stimuli may be a redox reaction, solvent addition, pH change, or light exposure. , The presented findings of such a controlled assembly process may yield interesting opportunities toward programmable, switchable and reconfigurable dynamic photonic materials for sensing, spatial light modulation and display applications . When applied to quantum dot materials, one may expect suitable properties toward reconfigurable lasers .…”

Recent advances in strongly resonant and gradient all-dielectric metasurfaces

“…Carrier photogeneration in HR-Si THz metasurfaces, optical phase change in photosensitive CG near-IR metasurfaces and electro-optical transmission modulation in SOH BIC near-IR metasurfaces are a few already experimentally proven concepts for the development of novel tunable components operating in different parts of the electromagnetic spectrum. A promising degree of freedom to dynamically adjust the metasurface response can be the mechanical tuning of its periodicity by employing a stretchable polymeric substrate as demonstrated in non-BIC dielectric metasurface examples 107 . Carrier injection, the Pockels or Kerr effect and the use of LC or phase-change materials can complete the picture and significantly broaden the spectrum of BIC metasurface functionalities for the engineering of novel devices spanning a broad range of emerging applications.…”

“…A promising degree of freedom to dynamically adjust the metasurface response is the mechanical tuning of its periodicity by employing a stretchable polymeric substrate as demonstrated in non-BIC dielectric metasurface examples. 107 Carrier injection, the Pockels or Kerr effect and the use of LC or phase-change materials can complete the picture and significantly broaden the spectrum of BIC metasurface functionalities for the engineering of novel devices spanning a broad range of emerging applications.…”

“…Tunable phase modulation in Huygens' qBIC metasurfaces was also theoretically proposed recently by employing an overlayer of nematic liquid crystal (LC) 106 . Thanks to their inherent large optical anisotropy and electro-optic response, as well as the mature display and LC-on-Si technology, LC have been as a versatile tunable medium in a large number of metadevices for applications where millisecond switching times are acceptable [107][108][109] . A tilted-ellipsoid qBIC metasurface was considered in contact with a LC overlayer between two indium-tin-oxide electrodes for the application of the bias voltage.…”

“…106 Thanks to their inherent large optical anisotropy and electro-optic response, as well as the mature display and LC-on-Si technology, LC has been demonstrated as a versatile tunable medium in a large number of metadevices for applications where millisecond switching times are acceptable. [107][108][109] A tilted-ellipsoid qBIC metasurface was considered in contact with a LC overlayer between two indium-tin-oxide electrodes for the application of bias voltage. Phase-only tuning was calculated in the full 2p range with a tuning bandwidth of around 3.5 nm, limited by the different shifting rates of the ED and MD qBIC resonances as a function of the anisotropic index tensor components.…”