# Non-Hermitian bulk–boundary correspondence in quantum dynamics

@article{Xiao2020NonHermitianBC, title={Non-Hermitian bulk–boundary correspondence in quantum dynamics}, author={Lei Xiao and Tianshu Deng and Kunkun Wang and Gaoyan Zhu and Zhong Wang and Wei Yi and Peng Xue}, journal={Nature Physics}, year={2020}, volume={16}, pages={761-766} }

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 systems. Recent theoretical studies indicate that this principle requires fundamental revisions for a wide range of open systems with effective non-Hermitian Hamiltonians. Therein, the intriguing localization of nominal bulk states at boundaries, known as the non-Hermitian skin effect, suggests a non…

## 280 Citations

Non-Hermitian bulk-boundary correspondence in a periodically driven system

- Physics
- 2020

Bulk-boundary correspondence, connecting the bulk topology and the edge states, is an essential principle of the topological phases. However, the bulk-boundary correspondence is broken down in…

Point-gap topology with complete bulk-boundary correspondence in dissipative quantum systems

- Physics
- 2020

The spectral and dynamical properties of dissipative quantum systems, as modeled by a damped oscillator in the Fock space, are investigated from a topological point of view. Unlike a physical lattice…

Point-gap topology with complete bulk-boundary correspondence and anomalous amplification in the Fock space of dissipative quantum systems

- PhysicsPhysical Review B
- 2021

The spectral and dynamical properties of dissipative quantum systems, as modeled by a damped oscillator in the Fock space, are investigated from a topological point of view. Unlike a physical lattice…

State-Dependent Topological Invariants and Anomalous Bulk-Boundary Correspondence in Non-Hermitian Topological Systems with Generalized Inversion Symmetry

- Physics, Mathematics
- 2020

The breakdown of the bulk-boundary correspondence in non-Hermitian (NH) topological systems is an open, controversial issue. In this paper, to resolve this issue, we ask the following question: Can a…

Selective and tunable excitation of topological non-Hermitian quasi-edge modes

- MathematicsProceedings of the Royal Society A
- 2022

Non-Hermitian lattices under semi-infinite boundary conditions sustain an extensive number of exponentially localized states, dubbed non-Hermitian quasi-edge modes. Quasi-edge states arise rather…

Exponentially growing bulk Green functions as signature of nontrivial non-Hermitian winding number in one dimension

- Physics, Mathematics
- 2020

A nonzero non-Hermitian winding number indicates that a gapped system is in a nontrivial topological class due to the non-Hermiticity of its Hamiltonian. While for Hermitian systems nontrivial…

Bulk-Boundary Correspondence for Non-Hermitian Hamiltonians via Green Functions.

- PhysicsPhysical review letters
- 2021

It is found that the non-Hermitian winding number in one dimension signals a topological phase transition in the bulk: It implies spatial growth of the bulk Green function.

Hybrid skin-topological modes without asymmetric couplings

- PhysicsPhysical Review B
- 2022

Non-Hermitian skin effect (NHSE) in non-Hermitian lattice systems, associated with a point gap on the complex energy plane, has attracted great theoretical and experimental interest. Much less is…

Unraveling non-Hermitian pumping: Emergent spectral singularities and anomalous responses

- Physics
- 2020

Within the expanding field of non-Hermitian physics, non-Hermitian pumping has emerged as a key phenomenon, epitomized through the skin effect via extensive boundary mode accumulation modifying the…

Quantum anomaly, non-Hermitian skin effects, and entanglement entropy in open systems

- Physics
- 2021

We investigate the roles of non-Hermitian topology in spectral properties and entanglement structures of open systems. In terms of spectral theory, we give a unified understanding of two…

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