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arXiv · 2412.14840

High-Efficiency spin-Seebeck Diode in an $α'$-Borophene FM/Normal/FM Nanoribbon Junction

F. Ghasemzadeh·M. Farokhnezhad·M. Esmaeilzadeh
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Abstract

The $α'$-borophene nanoribbon ($α'$-BNR), due to its incredible properties such as high stability and great mobility of carriers, demonstrates high efficiency in thermoelectric devices. We show that these properties enable us to produce a pure spin current by applying a temperature gradient with lower energy consumption in a ferromagnetic/normal/ferromagnetic (FM/Normal/FM) junction. Spin-dependent thermoelectric properties and spin-Seebeck are studied in this junction using the tight-binding (TB) formalism in combination with the non-equilibrium Green's function method (NEGF). The pure spin current due to the breaking of the electron-hole symmetry is induced in the system so that it can act as a spin-Seebeck diode. Moreover, the negative differential spin-Seebeck effect can be observed in the system. Finally, we show that, under the same conditions, the $α'$-BNR has a much higher power factor compared to that of graphene and silicene, which is due to the high asymmetry between the electrons and holes in the $α'$-BNR. The exceptional features of $α'$-BNR make it a very suitable choice for thermoelectric devices.

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F. Ghasemzadeh, M. Farokhnezhad, M. Esmaeilzadeh. 2026-07-16. High-Efficiency spin-Seebeck Diode in an $α'$-Borophene FM/Normal/FM Nanoribbon Junction. https://arxiv.org/abs/2412.14840

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