Beating the classical precision limit with spin-1 Dicke states of more than 10,000 atoms
Yi-Quan Zou, Ling-Na Wu, Qi Liu, Xinyu Luo, Shuai-Feng Guo, Jiahao Cao, Meng Khoon Tey, Li You · Proceedings of the National Academy of Sciences · 2018
Significance Entanglement is central to studies in foundations of quantum mechanics, quantum information, and precision measurement. Among the variety of multipartite entangled states, Dicke states form an important class, and their realizations attract widespread interest. Most of the Dicke states produced to date are limited to pseudospin-1/2 (two-level) particles. This work reports the generation of balanced Dicke states comprising spin-1 (three-level) atoms and the subsequent demonstration of enhanced interferometric sensitivity over the standard quantum limit facilitated by them. We expect it will stimulate both experimental and theoretical research efforts on entangled states of higher-spin particles.