Indirect controllability of two interacting qubits in presence of dissipation: a first analysis

We consider a bipartite open quantum system constituted by two interacting qubits
$A$
and
$B$
, assuming that the former is coupled to the environment and is directly affected by coherent control, while the latter does not interact directly with the environment and the control fields. We are interested in the controllability properties of the subsystem
$B$
. In this paper, we give a first analysis of the problem and provide some negative answers