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arXiv · 1612.07265

Non-equilibrium spin transport in integrable spin chains: persistent currents and emergence of magnetic domains

Andrea De Luca·Mario Collura·Jacopo De Nardis
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Abstract

We construct exact steady states of unitary non-equilibrium time evolution in the gapless XXZ spin-1/2 chain where integrability preserves ballistic spin transport at long-times. We characterize the quasi-local conserved quantities responsible for this feature and introduce a computationally effective way to evaluate their expectation values on generic matrix product initial states. We employ this approach to reproduce the long-time limit of local observables in all quantum quenches which explicitly break particle-hole or time-reversal symmetry. We focus on a class of initial states supporting persistent spin currents and our predictions remarkably agree with numerical simulations at long times. Furthermore, we propose a protocol for this model where interactions, even when antiferromagnetic, are responsible for the unbounded growth of a macroscopic magnetic domain.

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Andrea De Luca, Mario Collura, Jacopo De Nardis. 2016-12-21. Non-equilibrium spin transport in integrable spin chains: persistent currents and emergence of magnetic domains. https://doi.org/10.1103/physrevb.96.020403

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