Defect solitons supported by nonlocal PT symmetric superlattices
Laboratory of Nanophotonic Functional Materials and Devices, South China Normal University Guangzhou 510631, PRC
2 Department of Physics, Guangdong University of Petrochemical Technology - Maoming 525000, PRC
Accepted: 15 March 2012
The existence and stability of defect solitons supported by parity-time (PT) symmetric superlattices with nonlocal nonlinearity are investigated. In the semi-infinite gap, in-phase solitons are found to exist stably for positive or zero defects, but cannot exist in the presence of negative defects with strong nonlocality. In the first gap, out-of-phase solitons are stable for positive or zero defects, whereas in-phase solitons are stable for negative defects. The dependence of soliton stabilities on modulation depth of the PT potentials is studied. It is interesting that solitons can exist stably for positive and zero defects when the PT potentials are above the phase transition points.
PACS: 42.65.Tg – Optical solitons; nonlinear guided waves / 42.25.Bs – Wave propagation, transmission and absorption / 11.30.Er – Charge conjugation, parity, time reversal, and other discrete symmetries
© EPLA, 2012