  We study the beating effects of solitons in multi-component coupled
Bose-Einstein condensate systems. Our analysis indicate that the period of
beating behavior is determined by the energy eigenvalue difference in the
effective quantum well induced by solitons, and the beating pattern is
determined by the eigen-states of quantum well which are involved in the
beating behavior. We show that the beating solitons correspond to linear
superpositions of eigen-states in some quantum wells, and the correspondence
relations are identical for solitons in both attractive interaction and
repulsive interaction condensate. This provides a possible way to understand
the beating effects of solitons for attractive and repulsive interaction cases
in a unified way, based on the knowledge of quantum eigen-states. Moreover, our
results demonstrate many different beating patterns for solitons in
three-component coupled condensate, in sharp contrast to the beating dark
soliton reported before. The beating behavior can be used to test the
eigenvalue differences of some certain quantum wells, and more abundant beating
patterns are expected to exist in more components coupled systems.
