  This paper explores the utility of instantaneous and continuous observations
in the optimal control of quantum dynamics. Simulations of the processes are
performed on several multilevel quantum systems with the goal of population
transfer. Optimal control fields are shown to be capable of cooperating or
fighting with observations to achieve a good yield, and the nature of the
observations may be optimized to more effectively control the quantum dynamics.
Quantum observations also can break dynamical symmetries to increase the
controllability of a quantum system. The quantum Zeno and anti-Zeno effects
induced by observations are the key operating principles in these processes.
The results indicate that quantum observations can be effective tools in the
control of quantum dynamics.
