Drag force of Anisotropic plasma at finite $U(1)$ chemical potential
  We perform the calculation of drag force acting on a massive quark moving through an anisotropic ${\cal N}=4$ SU(N)= 4 SU(N) Super Yang-Mills plasma in the presence of a U(1) chemical potential. We present the numerical results for any value of anisotropy and arbitrary direction of the quark velocity with respect to the direction of anisotropy. We find the effect of chemical potential or charge density will enhance the drag force for the our charged solution. 
Long Cheng, Xian-Hui Ge, Shang-Yu Wu
hep-th