Non-Hermitian bulk-boundary correspondence in quantum dynamics
TLDR
In this paper, the non-Hermitian bulk-boundary correspondence was shown to hold for a wide range of open topological systems with effective non-Bloch Hamiltonians.Abstract:
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-Bloch band theory in which non-Bloch topological invariants are defined in generalized Brillouin zones, leading to a general bulk–boundary correspondence beyond the conventional framework. Here, we experimentally observe this fundamental non-Hermitian bulk–boundary correspondence in discrete-time non-unitary quantum-walk dynamics of single photons. We demonstrate pronounced photon localizations near boundaries even in the absence of topological edge states, thus confirming the non-Hermitian skin effect. Facilitated by our experimental scheme of edge-state reconstruction, we directly measure topological edge states, which are in excellent agreement with the non-Bloch topological invariants. Our work unequivocally establishes the non-Hermitian bulk–boundary correspondence as a general principle underlying non-Hermitian topological systems and paves the way for a complete understanding of topological matter in open systems. Measurements of non-Hermitian photon dynamics show boundary-localized bulk eigenstates given by the non-Hermitian skin effect. A fundamental revision of the bulk–boundary correspondence in open systems is required to understand the underlying physics.read more
Citations
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Topological optomechanical amplifier in synthetic PT $\mathcal{PT}$ -symmetry
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Two-body exceptional points in open dissipative systems
TL;DR: In this article , two-body non-Hermitian physics in the context of an open dissipative system depicted by the Lindblad master equation is studied, and the results not only demonstrate the interplay of PT symmetry and interaction on the exact few-body level, but also serve as a minimal illustration on how key features of non-hermitian many-body physics can be probed in a single-particle system.
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Non-Hermitian Floquet phases with even-integer topological invariants in a periodically quenched two-leg ladder
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Exceptional points in the one-dimensional Hubbard model
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Topological superconductors and exact mobility edges in non-Hermitian quasicrystals
TL;DR: In this article , the authors studied a class of non-Hermitian topological superconductors described by one-dimensional Aubry-Andr\'e Harper and mosaic quasiperiodic models with $p$-wave superconducting pairing.
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