Abstract:The steady-state nonvolatile two-step,two-color holographic recording performance with continuous-wave lights for LiNbO3:Fe:Mn was studied theoretically based on the two-center model.By comparing all of the different electron transfer processes between the deep-trap centers(Mn2 /Mn3 ) and the shallow-trap centers(Fe2 /Fe3 ),our results show that the direct electron exchange between the Mn2 /Mn3 and the Fe2 /Fe3 levels due to the tunneling effect dominates the amplitude of total space charge field under different experimental conditions in LiNbO3:Fe:Mn.This direct electron transfer process also plays a key role in the two-step,two-color holography performance of the crystal.