Defect modes are studied in parity-time (PT) symmetric periodic complex potentials for both positive and negative defects. Such new kinds of linear localized modes may conserve their energy or endure gain or loss upon propagating. The existence domain of the conserved modes would be prolonged by positive defects or shortened by negative defects, and the dissipative modes would appear before the phase transition point of the PT symmetric potential at stronger negative defects.
© 2010 Optical Society of America
Original Manuscript: April 9, 2010
Revised Manuscript: July 20, 2010
Manuscript Accepted: August 3, 2010
Published: August 25, 2010
Keya Zhou, Zhongyi Guo, Jicheng Wang, and Shutian Liu, "Defect modes in defective parity-time symmetric periodic complex potentials," Opt. Lett. 35, 2928-2930 (2010)