Department of Physics and MCTP, University of Michigan, Ann Arbor, Michigan 48109, USA.
Phys Rev Lett. 2011 Oct 28;107(18):180502. doi: 10.1103/PhysRevLett.107.180502. Epub 2011 Oct 27.
Dicke states represent a class of multipartite entangled states that can be generated experimentally with many applications in quantum information. We propose a method to experimentally detect genuine multipartite entanglement in the vicinity of arbitrary Dicke states. The detection scheme can be used to experimentally quantify the entanglement depth of many-body systems and is easy to implement as it requires measurement of only three collective spin operators. The detection criterion is strong as it heralds multipartite entanglement even in cases where the state fidelity goes down exponentially with the number of qubits.
狄克态表示一类多体纠缠态，可通过实验生成，在量子信息中有许多应用。我们提出了一种在任意狄克态附近实验检测真正多体纠缠的方法。该检测方案可用于实验量化多体系统的纠缠深度，且易于实现，因为它只需要测量三个集体自旋算符。该检测标准很强，即使在态保真度随量子比特数呈指数下降的情况下，也能预示多体纠缠。
