- Letter
- Open Access
Stochastic strong zero modes and their dynamical manifestations
Phys. Rev. E 107, L042104 – Published 28 April, 2023
DOI: https://doi.org/10.1103/PhysRevE.107.L042104
Abstract
Strong zero modes (SZMs) are conserved operators localized at the edges of certain quantum spin chains, which give rise to long coherence times of edge spins. Here we define and analyze analogous operators in one-dimensional classical stochastic systems. For concreteness, we focus on chains with single occupancy and nearest-neighbor transitions, in particular particle hopping and pair creation and annihilation. For integrable choices of parameters we find the exact form of the SZM operators. Being in general nondiagonal in the classical basis, the dynamical consequences of stochastic SZMs are very different from those of their quantum counterparts. We show that the presence of a stochastic SZM is manifested through a class of exact relations between time-correlation functions, absent in the same system with periodic boundaries.
Physics Subject Headings (PhySH)
- Classical mechanics
- Classical statistical mechanics
- Lattice dynamics
- Nonequilibrium statistical mechanics
- Stochastic processes
- 1-dimensional spin chains
- 1-dimensional systems
- Exclusion processes
- Lattice models in statistical physics
- Nonequilibrium lattice models
- Nonequilibrium systems
- Many-body techniques
- Monte Carlo methods
Article Text
Supplemental Material
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