A class of stable nonlinear non-Hermitian skin modes
- URL: http://arxiv.org/abs/2407.08880v1
- Date: Thu, 11 Jul 2024 21:55:01 GMT
- Title: A class of stable nonlinear non-Hermitian skin modes
- Authors: Hamed Ghaemi-Dizicheh,
- Abstract summary: The non-Hermitian skin effect (NHSE) is a well-known phenomenon in open topological systems.
NHSE causes a large number of eigenstates to become localized at the boundary.
This paper introduces a method for achieving a stable localized state in a nonlinear finite lattice.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: The non-Hermitian skin effect (NHSE) is a well-known phenomenon in open topological systems that causes a large number of eigenstates to become localized at the boundary. Although many aspects of its theory have been investigated in linear systems, this phenomenon remains novel in nonlinear models. In the first step of this paper, we look at the conditions for the presence of quasi-skin modes in a semi-infinite, one-dimensional, nonlinear, nonreciprocal lattice. In the following phase, we explore the survival time of the quasi-skin mode in a finite nonlinear lattice with open edges. We study the dependency of the survival time on the system's parameters and demonstrate how the nonreciprocity of the system affects the survival time. This study introduces a method for achieving a stable localized state in a nonlinear finite lattice.
Related papers
- Nonlinear skin modes and fixed-points [0.0]
We investigate a one-dimensional tight-binding lattice with asymmetrical couplings and various type of nonlinearities to study nonlinear non-Hermitian skin effect.
We identify distinctive features of nonlinear skin modes, such as power-energy dependence, degeneracy, and power-energy discontinuity.
arXiv Detail & Related papers (2024-11-19T11:22:42Z) - Exceptional Points and Stability in Nonlinear Models of Population Dynamics having $\mathcal{PT}$ symmetry [49.1574468325115]
We analyze models governed by the replicator equation of evolutionary game theory and related Lotka-Volterra systems of population dynamics.
We study the emergence of exceptional points in two cases: (a) when the governing symmetry properties are tied to global properties of the models, and (b) when these symmetries emerge locally around stationary states.
arXiv Detail & Related papers (2024-11-19T02:15:59Z) - On the Convergence of Gradient Descent for Large Learning Rates [55.33626480243135]
We show that convergence is impossible when a fixed step size is used.
We provide a proof of this in the case of linear neural networks with a squared loss.
We also prove the impossibility of convergence for more general losses without requiring strong assumptions such as Lipschitz continuity for the gradient.
arXiv Detail & Related papers (2024-02-20T16:01:42Z) - Dynamical chaos in nonlinear Schr\"odinger models with subquadratic
power nonlinearity [137.6408511310322]
We deal with a class of nonlinear Schr"odinger lattices with random potential and subquadratic power nonlinearity.
We show that the spreading process is subdiffusive and has complex microscopic organization.
The limit of quadratic power nonlinearity is also discussed and shown to result in a delocalization border.
arXiv Detail & Related papers (2023-01-20T16:45:36Z) - Sufficient condition for gapless spin-boson Lindbladians, and its
connection to dissipative time-crystals [64.76138964691705]
We discuss a sufficient condition for gapless excitations in the Lindbladian master equation for collective spin-boson systems.
We argue that gapless modes can lead to persistent dynamics in the spin observables with the possible formation of dissipative time-crystals.
arXiv Detail & Related papers (2022-09-26T18:34:59Z) - Harmonic oscillator kicked by spin measurements: a Floquet-like system
without classical analogous [62.997667081978825]
The impulsive driving is provided by stroboscopic measurements on an ancillary degree of freedom.
The dynamics of this system is determined in closed analytical form.
We observe regimes with crystalline and quasicrystalline structures in phase space, resonances, and evidences of chaotic behavior.
arXiv Detail & Related papers (2021-11-23T20:25:57Z) - Nonlinear non-Hermitian skin effect [0.0]
Distant boundaries in linear non-Hermitian lattices can dramatically change energy eigenvalues in a nonlocal way.
We show that fractal and continuum bands arise in a long lattice governed by a nonreciprocal discrete nonlinear Schrodinger equation.
We show that stationary solutions are localized at the edge in the continuum band.
arXiv Detail & Related papers (2021-06-08T11:32:22Z) - Long-lived period-doubled edge modes of interacting and disorder-free
Floquet spin chains [68.8204255655161]
We show that even in the absence of disorder, and in the presence of bulk heating, $pi$ edge modes are long lived.
A tunneling estimate for the lifetime is obtained by mapping the stroboscopic time-evolution to dynamics of a single particle in Krylov subspace.
arXiv Detail & Related papers (2021-05-28T12:13:14Z) - Hermitian zero modes protected by nonnormality: Application of
pseudospectra [0.0]
We develop a theory of zero modes with quantum anomaly for general Hermitian lattice systems.
We relate exact zero modes and quasi-zero modes of a Hermitian system to spectra and pseudospectra of a non-Hermitian system.
Our theory reveals the presence of nonnormality-protected zero modes, as well as the usefulness of the nonnormality and pseudospectra as tools for topological and/or non-Hermitian physics.
arXiv Detail & Related papers (2020-05-04T17:58:52Z) - Critical non-Hermitian Skin Effect [2.6109033135086777]
This work uncovers a new class of criticality where eigenenergies and eigenstates of non-Hermitian lattice systems jump discontinuously across a critical point in the thermodynamic limit.
We present stimulating examples with anomalous scaling behavior regarding spectrum, correlation functions, entanglement entropy, and scale-free wavefunctions that decay exponentially rather than power-law.
arXiv Detail & Related papers (2020-03-06T05:48:46Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.