  The rectification effect on the propagation of solitary waves in the
symmetric Y-shaped granular chain is numerically investigated in this Letter. A
heterojunction with mass mismatch occurs at the position of Y-junction by
adjusting the branch angle. And the heavy-light heterojunction is more
favorable for the solitary wave passing. The energy rectification efficiency
can be improved by adjusting the branch angle and the direction of incident
solitary wave. The results have particularly practical significance for the
potential design of acoustic diode devices.
