In this dissertation I analyze Hamiltonian control of
d-dimensional quantum systems as realized in alkali atomic spins. Alkali atoms provide an ideal platform for studies of quantum control due to the extreme precision with which the control fields are characterized as well as their isolation from their environment. In chapter 2, I review some background material on open-loop quantum control theory. Chapter 3 provides a derivation of the Hamiltonians arising from electromagnetic fields that we use to control our alkali atomic spins. In chapter 4, I develop an algorithm for state preparation, that is mapping a fiducial state to some arbitrary target state, and show numerical and experimental implementations for making arbitrary superpositions of hyperfine states in $^{133}Cs. Finally, chapter 5 presents a protocol for generating full unitary maps efficiently by utilizing the ability to construct state mappings.
We study the dynamics of a coupled cavity system composed of three cavities, and propose a scheme for the coherent manipulation of two collective atomic modes by a control atom. In the scheme, the control atom and two atomic ensembles interact with the local cavity mode, while the control atom is externally driven by a laser field. We show that under certain conditions, the dynamics of the whole system are reduced to an effective coherent coupling between the control atom and two collective atomic modes, while the cavity fields are only virtually excited. We also study the dynamics of the entanglement generation of the two distant collective atomic modes. The scheme provides a potential application for quantum-state engineering and quantum control.