Modulated reflectivity via a symmetrical metal cladding ferrofluids core waveguide chip Cheng Yin, Jingjing Sun, Xianping Wang, Changping Zhu, Qingbang Han, Ziyun Di and Zhuangqi Cao EPL, 100 4 (2012) 44001 Published online: 29 November 2012 DOI: 10.1209/0295-5075/100/44001