Photonic Bloch–dipole–Zener oscillations in binary parabolic optical waveguide arrays

We have studied the propagation and Zener tunneling of light in a binary parabolic optical waveguide array (BPOWA), which consists of two evanescently coupled dissimilar optical waveguides. Because of Bragg reflections, the BPOWA attains two minibands separated by a minigap at the zone boundary. Various coherent superpositions of optical oscillations and Zener tunneling occur for different parameters on the phase diagram. In particular, Bloch–Zener oscillation and a different type of Bloch–dipole–Zener oscillation are obtained by field-evolution analysis. The results may have potential applications in optical splitting and waveguiding devices and may shed light on the coherent phenomena in optical lattices.