Coherent spin-current oscillations in transverse magnetic fields.
نویسندگان
چکیده
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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عنوان ژورنال:
- Physical review letters
دوره 106 16 شماره
صفحات -
تاریخ انتشار 2011