Phase-dependent Andreev bound states and thermal transport in ferromagnetic-graphene Josephson junctions

Abstract

We theoretically investigate the phase-dependent properties of Andreev bound states and thermal transport in graphene-based superconducting–ferromagnetic–superconducting (SFS) Josephson junctions. Our results demonstrate that the spin-split Andreev bound states can be effectively modulated—opening and closing—by varying the strength of the ferromagnetic exchange field. The total thermal conductance of the junction is highly sensitive to changes in the exchange field. Furthermore, the thermal conductance at phase differences of ϕ=0 and ϕ=π exhibits pronounced oscillatory behavior as a function of both the exchange field and the junction length, alternating between distinct peaks and valleys. These findings indicate that SFS Josephson junctions based on graphene provide a promising platform for achieving controllable phase-coherent thermal transport.