Hopf Insulator Circuit

Topological phase in circuits

First experimental realization of the long-sought Hopf insulator in a 3D circuit system, verifying bulk-boundary correspondence.

Zhu, Wang · Zeng, Xu Tao · Biao, Yuanchuan · Yan, Zhongbo · Yu, Rui

Physical Review Letters 2023

Advantages

First experimental realization of Hopf insulator in a 3D circuit system

Hopf invariant equaling 4

Observed properties of bulk bands and topological surface states are in good agreement with theoretical predictions