Superconducting properties of novel BiSe$_{2}$-based layered   LaO$_{1-x}$F$_{x}$BiSe$_{2}$ single crystals
  F-doped LaOBiSe$_{2}$ superconducting single crystals with typical size of 2$\times$4$\times$0.2 mm$^{3}$ are successfully grown by flux method and the superconducting properties are studied. Both the superconducting transition temperature and the shielding volume fraction are effectively improved with fluorine doping. The LaO$_{0.48}$F$_{0.52}$BiSe$_{1.93}$ sample exhibits zero-resistivity at 3.7 K, which is higher than that of the LaO$_{0.5}$F$_{0.5}$BiSe$_{2}$ polycrystalline sample (2.4K). Bulk superconductivity is confirmed by a clear specific-heat jump at the associated temperature. The samples exhibit strong anisotropy and the anisotropy parameter is about 30, as estimated by the upper critical field and effective mass model 
Jifeng Shao, Zhongheng Liu, Xiong Yao, Lei Zhang, Li Pi, Shun Tan,   Changjin Zhang, and Yuheng Zhang
cond-mat.supr-con