Temperature-responded tunable metalenses based on phase transition materials

Once the metalenses are fabricated,the functions of most metalenses are invariable.The tunability and reconfigurability are useful and cost-saving for metalenses in realistic applications.We demonstrate this tunability here via a novel hybrid metalens with the strategic placement of an ultra-thin VO;layer.The hybrid metalens is capable of dynamically modulating the focusing intensity of transmitted light at a wavelength of 1550 nm,and demonstrate a 42.28%focusing efficiency of the incident light and 70.01%modulation efficiency.The hybrid metalens’optothermal simulations show an optothermal conversion process of dynamic focusing,and a maximum laser density of 1.76×10^(3)W/cm^(2) can be handled at an ambient temperature lower than 330 K.The hybrid metalens proposed in this work,a light-dose sensitive tunable smart metalens that can protect other instruments/systems or materials from being damaged,has its specific applications such as in anti-satellite blinding,bio-imaging,etc.