Quantum Zeno effect in quantum chaotic rotators

We analyzed the effect of frequent measurements on the quantum systems that are chaotic in the classical limit. It is shown that the delta-kicked rotator, a well-known example of quantum chaos, is too special to be used as a testing ground for the effects of the repeated measurements. The abrupt change of state vectors by the δ-function kick singular interruptions causes a quantum anti-Zeno effect. However, in more realistic rotators with interaction potentials of continuous time dependence, the quantum Zeno effect prevails.