Observation of Antichiral Edge States in a Circuit Lattice

Abstract

We constructed an electrical circuit to realize a modified Haldane lattice exhibiting the unusual phenomenon of antichiral edge states. The circuit consists of a network of inductors and capacitors with interconnections reproducing the effects of a magnetic vector potential. The next nearest neighbor hoppings are configured differently from the standard Haldane model, and as predicted by earlier theoretical studies, this gives rise to antichiral edge states that propagate in the same direction on opposite edges and co-exist with bulk states at the same frequency. Using pickup coils to measure the voltage distributions in the circuit, we experimentally verify the key features of the modified Haldane lattice, including the group velocities of the antichiral edge states.

Observation of Photonic Antichiral Edge States

“…The approach of on-site magnetization modulation may also provide a practical route to some predicted novel phenomena such as the one-way Klein tunneling [32]. Note added.-Recently, we found a recent preprint that reports the observation of antichiral edge states in a circuit network [33].…”

Non-Hermitian Skin Custers from Strong Interactions

“…Their dynamical study constitutes a particularly promising direction, with Hilbert space fragmentation known to lead to emergent violations of the eigenstate thermalization hypothesis (ETH) [20,86,87,90] and even quantum many-body scars [86,[91][92][93][94][95]. Appropriately generalized, our model may be physically realized with densityassisted tunneling in driven optical lattices [92,96], quantum digital computer circuits with suitably arranged imaginary time evolution [97,98], or, topolectrical circuits [31,44,[99][100][101][102][103][104][105] at the effective lattice level. We consider the zero mode in the effective SSH chain, expressed as ψ = (ψ 1A , ψ 1B , ...... ψ n−1A , ψ n−1B , ψ nA ) T (A,B are the labels of the sublattices in Fig.…”

Experimental realization of two-dimensional weak topological insulators

“…Recently, electronic circuits were demonstrated to be an excellent platform to simulate topological band physics. 23 Utilzing electronic components including resistances, inductors, capacitors, and operational amplifiers, one can study abundant topological phenomena, such as (higher-order) topological insulators, [24][25][26][27][28][29][30][31][32][33][34][35][36][37] semimetals, [38][39][40][41][42][43] and non-Hermitian physics, [44][45][46][47][48] among others. [49][50][51][52] In this Letter, we realize the WTIs in a spinless 2D Su-Schrieffer-Heeger (SSH) circuit under centrosymmetric deformations.…”