  Semiconductor quantum dots coherently driven by pulsed laser are fundamental
physical systems which allow studying the dynamical properties of confined
quantum states. These systems are attractive candidates for a solid-state
qubit, which open the possibility for several investigations in quantum
information processing. In this work we study the effects of a specific
decoherence process, the spontaneous emission of excitonic states, in a quantum
dot molecule. We model our system considering a three-level Hamiltonian and
solve the corresponding master equation in the Lindblad form. Our results show
that the spontaneous emission associated with the direct exciton helps to build
up a robust indirect exciton state. This robustness against decoherence allows
potential applications in quantum memories and quantum gate architectures. We
further investigate several regimes of physical parameters, showing that this
process is easily controlled by tuning of external fields.
