A. S. Sanz, C. Sanz-Sanz, T. Gonzalez-Lezana, O. Roncero, S. Miret-Artes
The behavior displayed by a quantum system when it is perturbed by a series
of von Neumann measurements along time is analyzed. Because of the similarity
between this general process with giving a deck of playing cards a shuffle,
here it is referred to as quantum shuffling, showing that the quantum Zeno and
anti-Zeno effects emerge naturally as two time limits. Within this framework, a
connection between the gradual transition from anti-Zeno to Zeno behavior and
the appearance of an underlying Markovian dynamics is found. Accordingly,
although a priori it might result counterintuitive, the quantum Zeno effect
corresponds to a dynamical regime where any trace of knowledge on how the
unperturbed system should evolve initially is wiped out (very rapid shuffling).
This would explain why the system apparently does not evolve or decay for a
relatively long time, although it eventually undergoes an exponential decay. By
means of a simple working model, conditions characterizing the shuffling
dynamics have been determined, which can be of help to understand and to devise
quantum control mechanisms in a number of processes from the atomic, molecular
and optical physics.
View original:
http://arxiv.org/abs/1112.3829
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