Edge magnetization and spin-valley-caloritronics in germanene and stanene nanoribbons

Abstract

We proposed a concept to generate the spin-valley Seebeck effect using the Kane-Mele-Hubbard model and electric field in zigzag nanoribbons. For this purpose, we apply a thermal gradient across the stanene and germanene nanoribbons. Then, we investigate the valley thermospin properties. Our results show that the edge magnetization can generate a controllable spin- and valley-polarized current by tuning the electric field in the silicene-like materials with large spin-orbit interaction. Moreover, a pure valley current is observed in a wide range of temperatures. Remarkably, we found that it is possible to produce the spin-valley-locked effect and high values of spin-valley Seebeck coefficients by controlling the chemical potential.