Angelo Russomanno, Alessandro Silva, Giuseppe E. Santoro
We study the coherent dynamics of a quantum Ising chain subject to a time-periodic transverse field which repeatedly crosses the quantum critical point. We find that after an initial transient, destructive interference in time makes the system synchronize with the perturbation: the quantum average of the observables becomes time-periodic, though keeping full memory of the initial state. As a result of interference, the system does not heat up indefinitely, and the "long-time" density of excitations is lower than the maximum one. Interference effects are moreover observed in the frequency dependence of the various observables, which display a sequence of well-defined peaks or dips.
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http://arxiv.org/abs/1204.5084
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