Translation and Rotation of Transformation Media under Electromagnetic   Pulse
  It is well known that optical media create artificial geometry for light, and curved geometry acts as an effective optical medium. This correspondence originates from the form invariance of Maxwells equations, which recently has spawned a booming field called transformation optics. Here we investigate responses of three transformation media under electromagnetic pulses, and find that pulse radiation can induce unbalanced net force on transformation media, which will cause translation and rotation of transformation media although their final momentum can still be zero. Therefore, the transformation media do not necessarily stay the same after an electromagnetic wave passes through. 
Fei Gao, Xihang Shi, Xiao Lin, Hongyi Xu, Baile Zhang
physics.optics