  We provide a characterization and analysis of the effects of dissipation on
oscillator assisted (qubus) quantum gates. The effects can be understood and
minimized by looking at the dynamics of the signal coherence and its
entanglement with the continuous variable probe. Adding loss in between
successive interactions we obtain the effective quantum operations, providing a
novel approach to loss analysis in such hybrid settings. We find that in the
presence of moderate dissipation the gate can operate with a high fidelity. We
also show how a simple iteration scheme leads to independent single qubit
dephasing, while retaining the conditional phase operation regardless of the
amount of loss incurred by the probe.
