Tunable optical angular selectivity in hyperbolic metamaterial via photonic topological transitions Jiang, Xiaoyun ; Wang, Tao ; Cheng, Le ; Zhong, Qingfang ; Yan, Ruoqin ; Huang, Xing Abstract Publication: Optics Express Pub Date: June 2019 DOI: 10.1364/OE.27.018970 Bibcode: 2019OExpr..2718970J