arXiv subjects

Wuping Yang

Publications and source records attributed to Wuping Yang.

3 recordsLinked to original sources

arXiv2026

Noise-Enhanced Self-Healing Dynamics in Non-Hermitian Systems

Self-healing is the ability of a wave packet to spontaneously restore its spatial profile after scattering. As an emergent feature of non-unitary dynamics, it has attracted significant interest in non-Hermitian physics. Here, we systematically investigate how stochastic noise influences edge self-healing. Counterintuitively, we find that noise can constructively enhance this dynamical process. Weak noise prolongs the self-healing window by aligning the finite-time Lyapunov exponent of the reference state with the maximum imaginary part of the energy spectrum. Remarkably, strong noise universally stabilizes asymptotic profile recovery across the entire spectrum by inducing an effective non-unitary drift-diffusion dynamics. We analytically elucidate these distinct mechanisms using a general finite-time Lyapunov exponent analysis, complemented by a dedicated perturbation theory for the strong-noise regime. Our results provide concrete guidance for realizing robust non-Hermitian dynamics in realistic noisy environments.

quant-ph↗

arXiv2026

Noise-Induced Resurrection of Dynamical Skin Effects in Quasiperiodic Non-Hermitian Systems

The non-Hermitian skin effect (NHSE) refers to the accumulation of an extensive number of eigenstates at system boundaries under open boundary conditions (OBCs). As a dynamical consequence, wave packets in such systems drift and ultimately accumulate at a boundary, giving rise to the dynamical skin effect (DSE). While strong quasiperiodic potentials are known to suppress the DSE by inducing localization, we show that the introduction of Ornstein-Uhlenbeck (OU) noise unexpectedly restores it. Using perturbative analysis, we demonstrate that noise effectively maps the non-Hermitian Schr\"{o}dinger dynamics onto a non-reciprocal master equation, whose complex spectrum develops a noise-induced point gap. This mechanism enables delocalization, reinstates directional transport, and revives the DSE even in regimes where the static NHSE is absent. Moreover, the relaxation dynamics exhibit a non-monotonic dependence on noise strength, reflecting a competition between noise-assisted delocalization and noise-induced decoherence. Our results uncover a noise-enabled mechanism for resurrecting the DSE and suggest a new route for controlling transport in quasiperiodic, open quantum systems.

quant-ph↗

arXiv2025

Unified Multipole Bott Indices for Non-Hermitian Skin Effect in Different Orders

Non-Hermitian systems exhibit a distinctive phenomenon known as the non-Hermitian skin effect, where an extensive number of eigenstates become localized at the boundaries of a lattice with open boundaries. While the spectral winding number under periodic boundary conditions is a well-established topological indicator for predicting the skin effect in one-dimensional non-Hermitian systems, a suitable topological invariant to diagnose higher-order skin effects remains elusive. In this Letter, we propose a unified non-Hermitian multipole characterization framework that generalizes the concept of spectral winding to higher-order skin effects. Specifically, we develop a set of non-Hermitian multipole Bott indices capable of diagnosing skin effects of different orders. Our approach provides a comprehensive understanding of both first- and higher-order skin effects in non-Hermitian systems, offering new perspectives for exploring topological phenomena in non-Hermitian systems.

cond-mat.mtrl-sci↗