Long-living photonic dipole oscillations in photonic crystals.

We investigate the occurrence of photonic dipole oscillations (PDOs) in one-dimensional photonic crystals containing nonlinear composites. Because of the modulation of the graded pump electric fields, optical pulses undergo oscillations inside the curved band structure, analogous to the dipole oscillations in ultracold gases. The implementation of numerical simulations shows that our proposed scheme can produce stable and long-living PDOs. The physical origin is explored to give a clear physical picture. Finally, the tunability of PDOs is discussed.