摘要
Adding a U(1) symmetry breaking term √V(λ1a0 + λ1*a0) + √V(λ2b0 + λ2*b0) to Bogoliubov's truncated Hamiltonian HB for a weakly interacting coupled Bose system, by using the mean-field approximation rather than the c-number approximation, we And that, via a Feshbach resonance at zero temperature, the states of the coupled Bose system are generalized SU(1,1) SU(1,1) coherent states. The Bose-Einstein condensation occurs in response to the spontaneous U(1) symmetry breaking.