Chen Tian, Zhang Shihao, Zhang Yi, Liu Yulong, Kou Su-Peng, Sun Houjun, Zhang Xiangdong
Key Laboratory of advanced optoelectronic quantum architecture and measurements of Ministry of Education, School of Physics, Beijing Institute of Technology, 100081, Beijing, China.
School of Information and Electronics, Beijing Institute of Technology, 100081, Beijing, China.
Nat Commun. 2019 Apr 5;10(1):1557. doi: 10.1038/s41467-019-09584-1.
Long-range entanglement is an important aspect of the topological orders, so efficient methods to characterize the long-range entanglement are often needed. In this regard, topological entanglement entropy (TEE) is often used for such a purpose but the experimental observation of TEE in a topological order remains a challenge. Here, we propose a scheme to observe TEE in the topological order by constructing specific minimum entropy states (MESs). We then experimentally construct the classical microwave analogs of the MESs and simulate the nontrivial topological order with the TEE in Kitaev toric code, which is in agreement with theoretical predictions. We also experimentally simulate the transition from Z topologically ordered state to topologically trivial state.
长程纠缠是拓扑序的一个重要方面，因此常常需要有效的方法来表征长程纠缠。在这方面，拓扑纠缠熵（TEE）常被用于此目的，但在拓扑序中对TEE进行实验观测仍然是一个挑战。在此，我们提出一种通过构建特定的最小熵态（MES）来在拓扑序中观测TEE的方案。然后，我们通过实验构建了MES的经典微波模拟物，并利用基塔耶夫环面码中的TEE模拟了非平凡拓扑序，这与理论预测相符。我们还通过实验模拟了从Z拓扑有序态到拓扑平凡态的转变。
