Controllable reconstruction of superhoneycomb plasma photonic crystals in air barrier discharges

Superhoneycomb lattice in photonics has many promising applications, such as conical diffraction and light localization. However, it remains a challenge to yield a tunable superhoneycomb lattice allowing for real-time control of its geometric configurations. Here, we experimentally demonstrate a novel tunable superhoneycomb plasma photonic crystal (ShPPC) via dielectric barrier discharge in ambient air. Rapid reconfiguration from the honeycomb lattice to various superhoneycomb lattices has been obtained. While large omnidirectional bandgaps (OBGs) can be obtained for ShPPCs, each ShPPC exhibits its own unique feature. A tunable topological ShPPC with valley-locked edge states has been proposed. An experimental verification of OBGs as well as their frequency shifting with the reconfiguration of different ShPPCs is presented. Moreover, a two-component phenomenological reaction diffusion model is utilized to reveal the formation mechanisms of ShPPCs. Experimental observations are in good agreement with numerical simulations. Our proposed ShPPCs hold potential implications for signal processing, optical switches, wireless communication, and optical information storage in dispersive materials.