I am glad to inform you that article entitled "Time evolution of two interacting charge qubits: entanglement and mean-field approach" by Sergey Filippov and Vladimir Vyurkov has finally appeared in the journal Quantum Computers and Computing 9(1), 60-65 (2009). This work was done during my Master Project in the Institute of Physics and Technology of the Russian Academy of Sciences (2007-2009). The full text is available (free access) at the publisher site.
The Coulomb interaction between charge qubits could be essential during the quantum computationprocedure. In order to demonstrate the sensitivity of quantum system dynamics to Coulomb interactionwe consider the general case of two interacting charge qubits. Though the time evolution of the systeminvolved is rather complex we show that it can be described by Hartree mean-field approach if one qubitis much faster than the other. Under this circumstance the initially separable state remains disentangledfor a very long time. The exact and approximate solutions are compared as well.