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arXiv · 1010.2351

Coherent spin-current oscillations in transverse magnetic fields

R. Steinigeweg·S. Langer·F. Heidrich-Meisner·I. P. McCulloch·W. Brenig
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Abstract

We address the coherence of the dynamics of spin-currents with components transverse to an external magnetic field for the spin-1/2 Heisenberg chain. We study current autocorrelations at finite temperatures and the real-time dynamics of currents at zero temperature. Besides a coherent Larmor oscillation, we find an additional collective oscillation at higher frequencies, emerging as a coherent many-magnon effect at low temperatures. Using numerical and analytical methods, we analyze the oscillation frequency and decay time of this coherent current-mode versus temperature and magnetic field.

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R. Steinigeweg, S. Langer, F. Heidrich-Meisner, I. P. McCulloch, W. Brenig. 2011-06-09. Coherent spin-current oscillations in transverse magnetic fields. https://doi.org/10.1103/physrevlett.106.160602

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