Solitons in PT-symmetric optical Mathieu lattices

We report the existence of stable optical spatial solitons in PT -symmetric optical Mathieu lattices. We find that Mathieu lattices allow a double phase transition between either having pure real or complex spectra by varying the particular continuous q parameter of the corresponding Mathieu lattice. We find that the q parameter can also modify the physical properties of the solitons, such as their shape, stability and dynamics. Moreover, this q parameter can be used to engineer the Mathieu lattice as an optical isolator for potential applications in light control.