# Observation of bulk boundary correspondence breakdown in topolectrical circuits

@inproceedings{Helbig2019ObservationOB, title={Observation of bulk boundary correspondence breakdown in topolectrical circuits}, author={Tobias Helbig and Tobias Hofmann and Stefan Imhof and Mohamed Abdelghany and Tobias Kie{\ss}ling and Laurens W. Molenkamp and Ching Hua Lee and Alexander Szameit and Martin Greiter and Ronny Thomale}, year={2019} }

The study of the laws of nature has traditionally been pursued in the limit of isolated systems, where energy is conserved. This is not always a valid approximation, however, as the inclusion of features like gain and loss, or periodic driving, qualitatively amends these laws. A contemporary frontier of meta-material research is the challenge open systems pose to the established characterization of topological matter1, 2. There, one of the most relied upon principles is the bulk-boundary…

## 28 Citations

### Non-Hermitian bulk–boundary correspondence in quantum dynamics

- PhysicsNature Physics
- 2020

Bulk–boundary correspondence, a guiding principle in topological matter, relates robust edge states to bulk topological invariants. Its validity, however, has so far been established only in closed…

### Bulk-edge correspondence of classical diffusion phenomena

- PhysicsScientific reports
- 2021

It is elucidate that diffusive systems, which are widely found in nature, can be a new platform of the bulk-edge correspondence, a representative topological phenomenon, and demonstrates the emergence of robust edge states protected by the winding number for one- and two-dimensional systems.

### Topological funneling of light

- PhysicsScience
- 2020

Using a time-dependent photonic lattice in which the topological properties can be controlled, Weidemann et al. show that such a structure can efficiently funnel light to the interface irrespective of the point of incidence on the lattice.

### Many-body topological and skin states without open boundaries

- PhysicsPhysical Review B
- 2021

Robust boundary states have been the focus of much recent research, both as topologically protected states and as non-Hermitian skin states. In this work, we show that many-body effects can also…

### Non-Hermitian Disorder-induced Topological insulators

- Physics
- 2019

Recent studies of disorder or non-Hermiticity induced topological insulators inject new ingredients for engineering topological matter. Here we consider the effect of purely non-Hermitian disorders,…

### Quenched topological boundary modes can persist in a trivial system

- PhysicsCommunications Physics
- 2021

Topological boundary modes can occur at the spatial interface between a topological and gapped trivial phase and exhibit a wavefunction that exponentially decays in the gap. Here we argue that this…

### Berry connection induced anomalous drift velocity in non-Hermitian systems

- Physics
- 2020

Berry phases strongly affect the properties of crystalline materials, giving rise to modifications of the semiclassical equations of motion that govern wave-packet dynamics. In non-Hermitian systems,…

### Dissipative analog of four-dimensional quantum Hall physics

- PhysicsPhysical Review Research
- 2020

Four-dimensional quantum Hall (QH) models usually rely on synthetic dimensions for their simulation in experiment. Here, we study a QH system which features a nontrivial configuration of…

### The Quantum Skin Hall Effect

- Physics
- 2020

The skin effect, which is unique to non-Hermitian systems, can generate an extensive number of eigenstates localized near the boundary in an open geometry. Here we propose that in 2D and 3D other…

### Nonreciprocal Transport of Exciton Polaritons in a Non-Hermitian Chain.

- PhysicsPhysical review letters
- 2020

This work considers exciton polaritons in a zigzag chain of coupled elliptical micropillars subjected to incoherent excitation and shows one-way information transfer, paving the way for compact and robust feedback-free one-dimensional polariton transmission channels without the need for external magnetic field.

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