Nonequilibrium spin transport in integrable spin chains: Persistent currents and emergence of magnetic domains

Journal article

We construct exact steady states of unitary nonequilibrium time evolution in the gapless XXZ spin-1/2 chain where integrability preserves ballistic spin transport at long times. We characterize the quasilocal 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.

Authors: De Luca, A; Collura, M; De Nardis, J

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review B
• Volume: 96
• Issue: 2
• Article number: 020403(R)
• Publication date: 2017-07-06
• DOI: 10.1103/PhysRevB.96.020403
• EISSN: 2469-9969
• ISSN: 2469-9950