P3S nanoribbons with bi-directional superior spin thermoelectric properties

To meet the demands of low-power micromaterials applications, the generation of pure spin currents in spintronics by utilizing an effective thermal spin conversion mechanism has become a hot topic among researchers. In this paper, based on the newly reported novel 2D P₃S monolayer, various P₃S nanoribbons with different edge atom arrangements are formed by one-dimensional tailoring. Intriguingly, the original nonmagnetism is broken in both armchair and zigzag orientations, introducing ferromagnetism contributed mainly by the 3p orbitals of the edge P atoms. More importantly, all bare nanoribbons exhibit peculiar transmission spectra with transmission peaks of opposite spin components located on both sides of the Fermi level. This apparent bipolar magnetic semiconductor property leads to a considerable spin Seebeck coefficient $S_s$ of ∼3 mV/K, which successfully suppresses the charge current and excites a giant spin current. Furthermore, the significant spin-dependent Seebeck effect is robust to width. The bi-directional superior spin thermoelectric properties, simple clipping method, and width robustness make the P₃S nanoribbons promising and competitive in spintronic devices.