摘要
The authors would like to apologize for an error in the paper Chinese Optics Letters vol. 15, no. 3, page 030010. On page 030010-3, the caption for Figs. 5 （a）-（c） should read ＂2 μm silica＂ （not 3 μm polystyrene）.
The authors would like to apologize for an error in the paper Chinese Optics Letters vol. 15, no. 3, page 030010. On page 030010-3, the caption for Figs. 5 （a）-（c） should read ＂2 μm silica＂ （not 3 μm polystyrene）.
