PHYSICAL REVIEW A VOLUME 59, NUMBER 2 FEBRUARY 1999 Local-field approach to the interaction of an ultracold dense bose gas with a light field +1)1-2-02-22921+G1( t=(-2+)2-1-22-h(△+的12+(2 绝数消去 h22 r)2「h P(r, t)=x(r, tEmae(r, t) xii(rn), (r. v,(rn) avi(r,t)v1(r,t) X(r,t)= dr,)1(r,n) V×V×E(r,) 8丌 1aE(r,)4丌a2p(r,t) +3a的h 4丌 a vy绝热消去