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  • Letter
  • Open Access

Stochastic strong zero modes and their dynamical manifestations

Katja Klobas1,*, Paul Fendley1,2, and Juan P. Garrahan3,4,2

  • 1Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
  • 2All Souls College, University of Oxford, Oxford, OX1 4AL, United Kingdom
  • 3School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom
  • 4Centre for the Mathematics and Theoretical Physics of Quantum Non-equilibrium Systems, University of Nottingham, Nottingham, NG7 2RD, United Kingdom

  • *katja.klobas@nottingham.ac.uk

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.

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