Details

Autor(en) / Beteiligte

• Qiao, Q
• Tan, F. X
• Yang, L. Y
• Yang, X. F
• Liu, Y. S

Titel

Largely enhanced thermoelectric effect and pure spin current in silicene-based devices under hydrogen modification

Ist Teil von

• Nanoscale, 2020-01, Vol.12 (1), p.277-288

Ort / Verlag

England: Royal Society of Chemistry

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Based on the density functional theory and nonequilibrium Green's function methods, we launch a systematic study of the magnetic properties and thermoelectric effects in silicene-based devices constructed by using zigzag silicene nanoribbons (ZSiNRs). By modulating the adsorption site, it is found that the ground state of ZSiNRs varies from an antiferromagnetic state to a ferromagnetic state. Meanwhile, a spin-degenerate semiconductor evolves into a spin semiconductor. The spin and charge thermoelectric figure of merits have an almost equal value of about 60 in the narrow device, which originates from the spin-dependent conductance dips and high spin-filtering effects. Moreover, a thermally-driven pure spin current in the silicene-based devices is obtained in the absence of the gate voltage, and its magnitude is effectively enhanced as the device width increases. Our results suggest that the silicene-based devices have very good prospects for spin caloritronics. (a) The theoretical model used to explain the physical mechanisms of the pure spin current. (b) The pure spin current versus the width of the spin caloritronic device.