Spin-dependent Seebeck effect in zigzag black phosphorene nanoribbons

As one of two-dimensional (2D) layered crystal materials, black phosphorene (BP) attracts wide interest due to its novel properties. To put BP towards device applications in spin caloritronics, here we investigate spin-dependent Seebeck effect (SDSE) in zigzag black phosphorene nanoribbons (ZBPNRs) by using first-principles calculations combined with non-equilibrium Green's function approach. The numerical results show that antiferromagnetic insulating states are stable in pristine ZBPNRs and ferromagnetic ZBPNR junctions can be constructed by an external magnetic field. By setting a different gradient between the source and the drain of the ZPNR junctions, spin-up and spin-down currents with nearly equal magnitudes are generated and flow in opposite directions, indicating that the SDSE occurs and the spin current dominates the carriers transport in the ZBPNRs. These results support that ZBPNRs are good candidates for the SDSE and have potential applications in future low-power-consumption technology.