Heat-pulse rectification in graphene Y junctions: A molecular dynamics simulations

• The heat-pulse rectification in graphene Y junctions is investigated by MD simulation.
• When the heat pulse flows from the stem to the branches, the transmission coefficient is more than twice that of the backward direction in the (A8-A4-A4, 120°) Y junction.
• The effect of different structures and the amplitude of the heat pulse have been studied.
• The anisotropic can be primarily attributed to the transverse vibrational modes.

By using molecular-dynamics simulations, we demonstrate the existence of heat-pulse rectification in graphene Y junctions. Our results show that the heat pulse will separate into two parts when it flows from stem to branches. However, when it flows from branches to stem, substantial part of the heat pulse is reflected back into the branches with no separation. Moreover, we discuss rectification in different type of junctions and find that the preferred heat pulse transport direction depends on the structure of the junctions, which enable us to delicately control the heat rectification in graphene based structures.