Two-dimensional anisotropic non-Hermitian Lieb lattice

We study an anisotropic two-dimensional non-Hermitian Lieb lattice, where the staggered gain and loss present in horizontal vertical directions, respectively. The intra-cell nonreciprocal coupling generates magnetic flux enclosed unit cell of lattice creates nontrivial topology. active dissipative topological edge states are along also supports passive corner state. At appropriate flux, non-Hermiticity can alter state from one to opposite as increases. gapless phase is characterized by different configurations exceptional points Brillouin zone. topology lattices be verified many experimental platforms including optical waveguide lattices, photonic crystals, electronic circuits.