Basedon the plane wave expansion, it can be written in the momentum space H=T+-7 2u(p, a,(Y p+M)u(p2, a2 )bpla1bp2a2 P1a1,P2,42,t y=∑∑(p1+q947(P1-9,4)(12)-2 P1p2, q a1, a2, t1 (p2,a2)(p12a1)bb PItg, ai P1q, 2 P2, 42 P1s a1 May 9, 2013@ USTCMay 9, 2013 @ USTC 1 2 2 1 1 , , , 1 2 *2 2 , , , , , 1 1 2 2 1 1 2 2 , , , , 1 1 1 2 2 2 1 1 , 1 1 2 1 2 2 1 2 1 1 1 2 2 ( , ) ( , ) q 1 ( , ) ( , ) (1,2) ( , )(γ p ) ( , ) 2 1 H T momentum space Basedon the plane waveexpansion, it can be written in the p q a p a p a i i p p q a a a a p a p a p a p a u p a u p a b b b b m V u p q a u p q a T u p a M u p a b b with V p q a + −  +   + +   + = +  −   =  + = +      