An Effective Two-component Entanglement in Double-well Condensation

We propose a spin-half approximation method for two-component condensation in double wells to discuss the quantum entanglement of two components. This approximation is presented to be valid under stationary tunneling effect for odd particle number of each component. The evolution of the entanglement is found to be affected by the particle number both quantitatively and qualitatively. In detail, the maximal entanglement are shown to be hyperbolic like with respect to tunneling rate and time. To successively obtain large and long time sustained entanglement, the particle number should not be large.