Perfect thermal spin filtering effect and excellent spin caloritronic properties in strain-modulated Janus VSTe monolayer

The spin caloritronic properties of the Janus VSTe monolayer were investigated using density functional theory (DFT) and the non-equilibrium Green’s function (NEGF) method, implemented in the Atomistix Toolkit (ATK) package. Our study revealed significant spin-splitting within the Janus VSTe monolayer, which induced spin currents under a temperature gradient across the device. By applying a 1% tensile strain, the Janus VSTe monolayer exhibited a perfect thermal spin filtering effect (SFE), with the spin-up current nearly suppressed to zero. Both the unstrained and strained Janus VSTe monolayers demonstrated excellent spin caloritronic properties, with spin figures of merit of 10.915 and 8.432 at an average temperature of 100 K, respectively. Notably, these properties were found to be sensitive to temperature, performing optimally at lower temperatures. These results suggest a promising avenue for designing spin caloritronic devices aimed at efficient waste heat recovery.