Adiabatic theorem for bipartite quantum systems in weak coupling limit

We study the adiabatic approximation of the dynamics of a bipartite quantum system with respect to one of its components, when the coupling between the two components is perturbative. We show that the density matrix of the considered component is described by adiabatic transport formulae exhibiting operator-valued geometric and dynamical phases. The present results can be used to study the quantum control of the dynamics of qubits and of open quantum systems where the two components are the system and its environment. We treat two examples, the control of an atomic qubit interacting with another one and the control of a spin in the middle of a Heisenberg spin chain.