The mechanism of the efficiency enhancement is that the tapered magnetic field changes the condition of the electrons motion and improves the bunching of the electrons in the interaction between the electron beam and the wave.

• 这种效率放大的物理机制是2坡度磁场改变了相对论电子的运动条件，有效地改善了波束互作用过程中电子的群聚状态，使电子束有更多的动能转换为电磁能，从而提高了电子束的换能效率。