论文标题
特殊点的发散量子度量的实验测量
Experimental measurement of the divergent quantum metric of an exceptional point
论文作者
论文摘要
哈密顿特征状态的几何形状编码在量子几何张量（QGT）中。它既包含浆果曲率，这是拓扑问题描述和量子度量标准的核心。到目前为止，仅在Hermitian系统中测量了完整的QGT，在Hermitian系统中，量子指标的作用主要显示以确定对物理效应的校正。相反，在非炎症系统，尤其是附近的特殊点中，量子指标有望发散并经常发挥主导作用，例如在增强的感应和波数据包动力学上。在这项工作中，我们报告了非富米系统中量子指标的第一个实验测量。所研究的特定平台是具有激子 - 波利顿特征状态的有机微腔，其表现出了特殊的点。我们测量量子指标的差异，并确定缩放指数$ n = -1.01 \ pm0.08 $，这与二阶特殊点的理论预测一致。
The geometry of Hamiltonian's eigenstates is encoded in the quantum geometric tensor (QGT). It contains both the Berry curvature, central to the description of topological matter and the quantum metric. So far the full QGT has been measured only in Hermitian systems, where the role of the quantum metric is mostly shown to determine corrections to physical effects. On the contrary, in non-Hermitian systems, and in particular near exceptional points, the quantum metric is expected to diverge and to often play a dominant role, for example on the enhanced sensing and on wave packet dynamics. In this work, we report the first experimental measurement of the quantum metric in a non-Hermitian system. The specific platform under study is an organic microcavity with exciton-polariton eigenstates, which demonstrate exceptional points. We measure the quantum metric's divergence and we determine the scaling exponent $n=-1.01\pm0.08$, which is in agreement with theoretical predictions for the second-order exceptional points.
