[1] Chiao R Y, Garmire E, Townes C H. Self-trapping of optical beam[J]. Physical Review Letters,1964,13: 479-484.
[2] Kivshar Y S, Agrawal G P. Optical solitons: From fibers to photonic crystals[M]. San Diego: Academic Press, 2003: 3-5.
[3] Zhang Jiefang, Zhao Bi, Hu Wencheng, et al. Interaction propagation of optical vortex solitons in inhomogeneous nonlinear waveguides[J]. Acta Optica Sinica, 2013, 33(4): 0419001.
[4] Yu Wensu, Qin Yali, Ren Hongliang, et al. Research on ring-like vortex solitons in Bessel lattices[J]. Acta Optica Sinica, 2014, 34(7): 0719001.
[5] Yan Man, Qin Yali, Liu Xian, et al. Propagation of double-charge vortex beam in a negative defect photonic lattice[J]. Laser & Optoelectronics Progress, 2015, 52(8): 081904.
[6] Yang Bin, Qin Yali, Liu Xian, et al. Research on dipole solitons in optically induced lattices[J]. Acta Optica Sinica, 2015, 35(7): 0719001.
[7] Dong L W, Ye F W. Stability of multipole-mode solitons in thermal nonlinear media[J]. Physical Review A, 2010, 81(1): 013815.
[8] Wen Z C, Yan Z Y. Dynamical behaviors of optical solitons in parity-time (PT) symmetric sextic anharmonic double-well potentials[J]. Physical Letters A, 2015, 379(36): 2025-2029.
[9] Musslimani Z H, Makris K G, El-Ganainy R, et al. Optical solitons in PT periodic potentials[J]. Physical Review Letters, 2008, 100: 030402.
[10] Bender C M, Boettcher S. Real spectra in non-Hermitian Hamiltonians having PT symmetry[J]. Physical Review Letters, 1998, 80: 5243-5246.
[11] Guo A, Salamo G J, Duchesne D, et al. Observation of PT-symmetric breaking in complex optical potentials[J]. Physical Review Letters, 2009, 103: 093902.
[12] Rueter C E, Makris K G, EI-Ganainy R, et al. Observation of parity-time symmetry in optics[J]. Nature Physics, 2010, 6: 192-195.
[13] Hu S, Ma X, Lu D, et al. Solitons supported by complex PT-symmetric Gaussian potentials[J]. Physical Review A, 2011, 84(4): 21098-21108.
[14] Hu S, Ma X, Lu D, et al. Defect solitons in parity-time symmetric optical lattices with nonlocal nonlinearity[J]. Physical Review A, 2012, 85(4): 2212-2222.
[15] Fang L, Gao J, Shi Z, et al. Nonlocal defect solitons in parity-time-symmetric superlattices with defocusing nonlinearity[J]. The European Physical Journal D, 2014, 68(10): 1-5.
[16] Liu S, Ma C, Zhang Y, et al. Bragg gap solitons in PT symmetric lattices with competing nonlinearity[J]. Optics Communications, 2012, 285(7): 1934-1939.
[17] Zhou Bozhen, Hua Chunbo, Xu Siliu, et al. Optical vortex soliton in parity-time symmetric potentials[J]. Chinese J Lasers, 2015, 42(5): 0505004.
[18] Achilleos V, Kevrekidis P G, Frantzeskakis D J, et al. Dark solitons and vortices in PT-symmetric nonlinear media: From spontaneous symmetry breaking to nonlinear PT phase transitions[J]. Physical Review A, 2012, 86(1): 013808.
[19] Kartashov Y V, Malomed B A, Torner L. Unbreakable PT symmetry of solitons supported by inhomogeneous defocusing nonlinearity[J]. Optics Letters, 2014, 39(19): 5641-5644.
[20] Khawaja U Al, Al-marzoug S M, Bahlouli H, et al. Unidirectional soliton flows in PT-symmetric potentials[J]. Physical Review A, 2013, 88(2): 023830.
[21] Zhou K, Wei T, Sun H, et al. Soliton dynamics in a PT-symmetric optical lattice with a longitudinal potential barrier[J]. Optics Express, 2015, 23(13): 16903-16911.