Specular Andreev reflection in graphene-based superconducting junction with substate-induced spin orbit interaction

• The retro-Andreev reflection in graphene is suppressed by the spin orbit interaction.
• The specular Andreev reflection in graphene can be enhanced largely by the spin orbit interaction.
• The Fabry–Perot interferences in the graphene-based barrier lead to the oscillating feature of the tunneling conductance.
• The spin orbit interaction is also vital in diagnosing the specular Andreev reflection in graphene.

Based on the Dirac–Bogoliubov–de Gennes equation, the chirality-resolved transport properties through a ballistic graphene-based superconducting heterojunction with both the Rashba and the Dresselhaus spin orbit interaction have been investigated. Our results show that, in contrast to the retro-Andreev reflection suppressed by the spin orbit interaction (SOI), the specular Andreev reflection (SAR) can be enhanced largely by the SOI. Moreover, the Fabry–Perot interferences in the barrier region lead to the oscillating feature of the tunneling conductance. It is anticipated to apply the qualitative different results to diagnose the SAR in single layer graphene in the presence of both kinds of the SOI.