[2] M.-A. Miri, A. Alù. Exceptional points in optics and photonics. Science, 363, eaar7709(2019).
[4] S. Kharitonov, C. Brés. Dual-emission band all-fiber laser based on theta cavity with thulium- and holmium-doped fibers. Optical Fiber Communications Conference and Exhibition (OFC), 1-3(2017).
[11] B. E. A. Saleh, M. C. Teich. Fundamentals of Photonics(2007).