Mean-field dynamics for mixture condensates via Fock space methods

We consider a mean-field model to describe the dynamics of N1 bosons of species one and N2 bosons of species two in the limit as N1 and N2 go to infinity. We embed this model into Fock space and use it to describe the time evolution of coherent states which represent two-component condensates. Following this approach, we obtain a microscopic quantum description for the dynamics of such systems, determined by the Schrödinger equation. Associated to the solution to the Schrödinger equation, we have a reduced density operator for one particle in the first component of the condensate and one particle in the second component. In this paper, we estimate the difference between this operator and the projection onto the tensor product of two functions that are solutions of a system of equations of Hartree type. Our results show that this difference goes to zero as N1 and N2 go to infinity.