Determining topological charge based on an improved Fizeau interferometer Cui, Shengwei ; Xu, Bin ; Luo, Saiyu ; Xu, Huiying ; Cai, Zhiping ; Luo, Zhengqian ; Pu, Jixiong ; Chávez-Cerda, Sabino Abstract Publication: Optics Express Pub Date: April 2019 DOI: 10.1364/OE.27.012774 Bibcode: 2019OExpr..2712774C