RT Journal T1 Photonic crystals and topological photonics A1 C.T. CHAN PB Front. Optoelectron. FD 2020-03-15 YR 2020 JF Frontiers of Optoelectronics JO Front. Optoelectron. VO 13 IS 1 SP 2 DO 10.1007/s12200-020-1022-2 K1 LK {https://journal.hep.com.cn/foe/EN/article/article_27040.shtml}