[1] D. J. Doran, D. Wood. Nonlinear-optical loop mirror. Opt. Lett., 1988, 13(1): 56～58

[2] M. E. Fermann, F. Habert, M. Hofer et al.. Nonlinear amplifying loop mirror. Opt. Lett., 1990, 15(10): 752～754

[3] H. A. Haus, E. P. Ippen, K. Tamura. Additive-pulse modelocking in fiber lasers. IEEE J. Quant. Electron., 1994, QE-30(1): 200～208

[4] H. Lin, D. K. Donald, W. V. Sorin. Optimizing polarization states in a figure-8 laser using a nonreciprocal phase shifer. J. Lightwave Technol., 1994, 12(7): 1121～1128

[5] B. C. Barnett, L. Rahamn, M. N. Islam et al.. High-power erbium-doped fiber laser mode locked by a semiconductor saturable absorber. Opt. Lett., 1995, 20(5): 471～473

[6] A. Yu, A. S. Siddiqui. Optical modulators using fiberoptic sagnac interferometers. IEE Proc Optoelectron., 1994, 141(1): 1～7

[7] T. A. Birks, P. Morkel. Jones calculus analysis of single-mode fiber Sagnac reflector. Appl. Opt., 1988, 27(15): 3107～3113

[8] R. McBride, J. D. C. Jones. A passive phase recovery technique for Sagnac interferometer based on controlled loop birefringence. J. Mod. Optics, 1992, 39(6): 1309～1320

[9] A. J. Stentz, R. W. Boyed. Polarization effects and nonlinear switching in fiber figure-eight lasers. Opt. Lett., 1994, 19(18): 1462～1464