Reply to Comment on "Space-Time Crystals of Trapped Ions"
  This is a reply to the comment from Patrick Bruno (arXiv:1211.4792) on our paper (Phys. Rev. Lett. 109, 163001 (2012)). 
Tongcang Li, Zhe-Xuan Gong, Zhang-Qi Yin, H. T. Quan, Xiaobo Yin, Peng   Zhang, L.-M. Duan, Xiang Zhang
quant-ph cond-mat.quant-gas physics.atom-ph