Sankar Sarath, Sela Eran, Han Cheolhee
School of Physics and Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel.
Phys Rev Lett. 2023 Jul 7;131(1):016601. doi: 10.1103/PhysRevLett.131.016601.
Topological entanglement entropy (TEE) is a key diagnostic of topological order, allowing one to detect the presence of Abelian or non-Abelian anyons. However, there are currently no experimentally feasible protocols to measure TEE in condensed matter systems. Here, we propose a scheme to measure the TEE of chiral topological phases, carrying protected edge states, based on a nontrivial connection with the thermodynamic entropy change occurring in a quantum point contact (QPC) as it pinches off the topological liquid into two. We show how this entropy change can be extracted using Maxwell relations from charge detection of a nearby quantum dot. We demonstrate this explicitly for the Abelian Laughlin states, using an exact solution of the sine-Gordon model describing the universal crossover in the QPC. Our approach might open a new thermodynamic detection scheme of topological states also with non-Abelian statistics.
拓扑纠缠熵（TEE）是拓扑序的关键诊断指标量断方法，能让人检测阿贝尔任意子或非阿贝尔任意子的存在。然而，目前在凝聚态系统中尚无实验上可行的测量TEE的方案。在此，我们提出一种方案，基于与量子点接触（QPC）将拓扑液体挤压成两部分时发生的热力学熵变的非平凡关联，来测量具有受保护边缘态的手征拓扑相的TEE。我们展示了如何利用麦克斯韦关系从附近量子点的电荷检测中提取这种熵变。我们使用描述QPC中通用交叉的正弦 - 戈登模型的精确解，对阿贝尔劳克林态明确地证明了这一点。我们的方法可能也会开启一种针对具有非阿贝尔统计的拓扑态的新的热力学检测方案。
