论文标题
广义Pancharatnam-Berry阶段的拓扑过渡
Topological transitions of the generalized Pancharatnam-Berry phase
论文作者
论文摘要
与动态阶段不同的是，在循环演化中，系统的状态可能会获取附加成分，又称几何阶段。后者是状态空间中封闭路径的表现。几何阶段是各种物理现象的基础，尤其是多体状态的拓扑不变的出现。最近，已经证明几何阶段可以通过在单个量子位上实现的一系列广义测量序列诱导。此外，已经预测，这种几何阶段可能会表现出拓扑转变作为测量强度的功能。在这里，我们通过光学平台在实验上证明并研究了这一过渡。我们展示了原始协议的某些概括以及某些类型的缺陷的鲁棒性。我们的协议可以用环境引起的几何阶段来解释。
Distinct from the dynamical phase, in a cyclic evolution, a system's state may acquire an additional component, a.k.a. geometric phase. The latter is a manifestation of a closed path in state space. Geometric phases underlie various physical phenomena, notably the emergence of topological invariants of many-body states. Recently it has been demonstrated that geometric phases can be induced by a sequence of generalized measurements implemented on a single qubit. Furthermore, it has been predicted that such geometric phases may exhibit a topological transition as function of the measurement strength. Here, we demonstrate and study this transition experimentally employing an optical platform. We show the robustness to certain generalizations of the original protocol, as well as to certain types of imperfections. Our protocol can be interpreted in terms of environment-induced geometric phases.
