Adsorption of Ti atoms on zigzag silicene nanoribbons: influence on electric, magnetic, and thermoelectric properties

Abstract

We study the adsorption effects of Ti atoms on the physical properties of zigzag silicene nanoribbons using the density functional theory combined with the nonequilibrium Green's function methods. The adsorption geometries, conductance spectra, current voltage curves, spin polarizations, magnetoresistance, and Seebeck coefficients are evaluated in different adsorption samples. Ti adatoms prefer sites inside the nanoribbons instead of on the edges. Two neighboring adatoms are attractively coupled and prefer being adsorbed on the same side. The giant magnetoresistance in nanoribbons of even width is usually greatly reduced, except in symmetric adsorption cases. Strong spin negative differential resistance phenomena can be observed and pure spin current can be produced by temperature gradient in specific cases.