Fig. 2: Observation of the topological Bloch oscillations on electric circuits.
From: Three-dimensional non-Abelian Bloch oscillations and higher-order topological states
a A schematic diagram of the designed circuit for the 3D higher-order topological insulator model with an applied force. b The internal structure of a circuit site with two nodes and their grounding parts. c The structure of the negative impedance converter with current inversion. d, e Connections between different sites for positive and negative hopping terms, respectively. f–h Simulation (red solid line) and experimental results (green dotted lines with error bars) for the center of mass of the circuit wavepacket in x, y, and z directions, respectively. The circuit is constructed for a lattice model with a finite size of 3 × 3 × 3 unit cells and an applied force of Fx = Fy = Fz = –0.4J1. Here J2 = 0.1J1 and J1, J2 are the intracell and intercell hopping amplitudes, respectively. The error bars are obtained from the average with data from 10 groups. i Simulation (red solid line) and experimental results (green dots) of real-space wavepacket trajectory. j Experimental results of Band occupation dynamics in momentum space.
