Multipurpose thermoresponsive hydrogel: a platform for dynamic holographic display

Metamaterials have shown great promise for manipulating electromagnetic (EM) waves, thus opening new routes for the progression of flat optics. However, postfabrication fixed structures hinder the dynamic manipulation of light. Dynamic control of EM light has been realized through different mechanisms including electrical gating, optical pumping, mechanical actuation, and temperature stimulation. Here, we are first proposing the plasmonic-resonators-mounted thermoresponsive free-standing hydrogel for holographic display that swells and collapses laterally by temperature. By taking leverage of reversible switching of the hydrogel, we numerically examine the polarization-insensitive dynamic holographic switch by a plasmonic-rings/discs-loaded hydrogel in reflection as a primary application. Second, we observe the transmissive functionality of a plasmonic-sector-resonators-mounted hydrogel, which displays a persistent holographic image under swelling and collapsing conditions. This work demonstrates the potential of a resonators-loaded thermoresponsive hydrogel for EM wave manipulation including dynamic holography, active lensing, switching, and so on.