



@article {1491,
	title = {Reply to Comment on "Space-Time Crystals of Trapped Ions},
	year = {2012},
	month = {2012/10/15},
	abstract = {  This is a reply to the comment from Patrick Bruno (arXiv:1211.4792) on our
paper (Phys. Rev. Lett. 109, 163001 (2012)).
},
	doi = {http://dx.doi.org/10.1103/PhysRevLett.109.163001},
	url = {http://arxiv.org/abs/1212.6959v2},
	author = {Tongcang Li and Zhe-Xuan Gong and Zhang-qi Yin and H. T. Quan and Xiaobo Yin and Peng Zhang and L. -M. Duan and Xiang Zhang}
}
@article {1794,
	title = {Space-Time Crystals of Trapped Ions},
	journal = {Physical Review Letters},
	volume = {109},
	year = {2012},
	month = {2012/10/19},
	pages = {163001},
	abstract = {Spontaneous symmetry breaking can lead to the formation of time crystals, as well as spatial crystals. Here we propose a space-time crystal of trapped ions and a method to realize it experimentally by confining ions in a ring-shaped trapping potential with a static magnetic field. The ions spontaneously form a spatial ring crystal due to Coulomb repulsion. This ion crystal can rotate persistently at the lowest quantum energy state in magnetic fields with fractional fluxes. The persistent rotation of trapped ions produces the temporal order, leading to the formation of a space-time crystal. We show that these space-time crystals are robust for direct experimental observation. We also study the effects of finite temperatures on the persistent rotation. The proposed space-time crystals of trapped ions provide a new dimension for exploring many-body physics and emerging properties of matter.},
	doi = {10.1103/PhysRevLett.109.163001},
	url = {http://link.aps.org/doi/10.1103/PhysRevLett.109.163001},
	author = {Tongcang Li and Gong, Zhe-Xuan and Yin, Zhang-Qi and Quan, H. T. and Yin, Xiaobo and Zhang, Peng and Duan, L.-M. and Zhang, Xiang}
}
