The atom-photon entanglement of a two-level system embedded in double-band photonic band edge

► Numerical simulations of the entanglement of a two-level atom with its spontaneously emitted photon embedded in double-band anisotropic photonic crystal. ► Different from the cases of isotropic crystals or vacuum, the entanglement has symmetrical properties and much slower entanglement rate near the two band edges. ► The entanglement is gradually increasing as the atomic frequency moves from the center of the forbidden gap to either of the band edge.