FIG. 1: (color online). The entanglement degree of the initial state | φ 〉 for different α$_{1}$ and α$_{2}$ . defined as follows Here I a form a su (3) algebra characterized by f$_{abc}$ , { F a i , a = 1 , · · · , 8 } form a local su (3) on the i site, and are equal to half of the corresponding Gell-Mann matrices, µ , ν , λ are parameters or Casimir operators and ω$_{ij}$ = − ω$_{ji}$ which satisfies A more practical expression is expressed as Here J a ( a = 1 , · · · , 8) are the generators of Y ( su (3)). Due to the transition effect of Yangian generators, transition operators P can be con- structed as compositions of the generators in Eq. (6). P can be looked upon as a function of ¯ I ± , ¯ U ± , ¯ V ± , ¯ I 3 and ¯ I $^{8}$, namely, P = F [ ¯ I ± , ¯ U ± , ¯ V ± , ¯ I $^{3}$, ¯ I $^{8}$]. When acting the transition op- erator on | φ 〉 in Eq. (1), a final state | φ $^{′}$〉 = P | φ 〉 can be gotten and its entanglement degree C$_{φ}$ ′ can also be calculated out via Eq.(2). Different final states with desired entanglement degrees thus can be gotten by acting corresponding transition operators on initial states. In order to illustrate this issue clearly, several simple examples are going to be discussed in more detail. 4 ¯ I ± = J $^{1}$± iJ $^{2}$, ¯ U ± = J $^{6}$± iJ $^{7}$, ¯ V ± = J $^{4}$± iJ $^{5}$, ¯ I 3 = J $^{3}$, ¯ I 8 = 2 √$_{3}$ J $^{8}$. (6) ω$_{ij}$ =      1 i>j − 1 i<j 0 i = j . (5) I a = ∑ i F a i , J a = µI a 1 + νI a 2 + i 2 λf$_{abc}$ ∑ i = j ω$_{ij}$I b $_{i}$I c j ( i, j = 1 , 2) . (4) -0.5 0 0.5 Α$_{1}$ -0.5 0 0.5 Α$_{2}$ 0 0.25 0.5 0.75 1 C$_{Φ}$