Realization of tunable plasma Lieb lattice in dielectric barrier discharges

Lieb lattice has been proven to host various extraordinary properties due to its unique Dirac-flat band structure. However, the realization of tunable Lieb lattices with controllable configurations still remains a significant challenge. We demonstrate the first realization of a robust and tailorable plasma Lieb lattice in dielectric barrier discharges by the use of uniquely designed mesh-water electrodes. Fast reconfiguration between square lattice, Lieb lattice, and various Lieb superlattices has been achieved in a wide range of discharge parameters even in ambient air. Active control of the symmetry, size, and fine structures of plasma elements in Lieb lattices is realized. Three distinct discharge stages in plasma Lieb lattice are proposed on the basis of fast camera diagnostics. The Dirac-flat band structure of the plasma Lieb lattice is demonstrated. Experimental verification of the photonic bandgap for the Lieb lattice is provided. Moreover, the Gierer–Meinhardt reaction diffusion model with spatial modulations is established to simulate the formation of different Lieb lattices. Experimental observations and numerical simulations are in good agreement. The results provide an important step forward in the ongoing effort to realize tunable Lieb lattices, which may find promising applications in the manipulation of microwaves.