We study the possibility to undo the quantum mechanical evolution in a time reversal experiment. The naive expectation, as reflected in the common terminology (“Loschmidt echo”), is that maximum compensation results if the reversed dynamics extends to the same time as the forward evolution. We challenge this belief and demonstrate that the time [Formula presented] for maximum return probability is in general shorter. We find that [Formula presented] depends on [Formula presented], being the ratio of the error in setting the parameters (fields) for the time-reversed evolution to the perturbation which is involved in the preparation process. Our results should be observable in spin-echo experiments where the dynamical irreversibility of quantum phases is measured.
|Original language||English GB|
|Number of pages||1|
|Journal||Physical Review Letters|
|State||Published - 1 Jan 2004|
ASJC Scopus subject areas
- Physics and Astronomy (all)