Energy sharing induced by the nonlinear interaction

Strong energy sharing is shown by numerically investigating coupled multi-component Bose-Einstein condensates (BECs) with a harmonic trap to simulate the Fermi-Pasta-Ulam model (FPU). For two-component BECs, the energy exchanging between each part, from regular, quantum beating to complete energy sharing, is explored by simulating their Husimi distributions, the time evolution of energies and the statistical entropy. Meanwhile, in the three-component case, a more complex energy sharing behavior is reported and a strong energy sharing is found.