Giant rectification of ferromagnetic zigzag SiC nanoribbons connecting anthradithiophene molecules

Abstract

Using non-equilibrium Green's function combined with density functional theory, we investigate the spin-resolved transport properties of the zigzag SiC nanoribbon (zSiCNR) connecting anthradithiophene (ADT) molecules and obtain the giant spin current rectification in the presence of a ferromagnetic field. The dual-hydrogenation on edge C atoms or Si atoms can change the initial metallicity of the pristine zSiCNR with the edge mono-hydrogenation into semiconductivity in the presence of a ferromagnetic field. The up-spin current-voltage characteristic of the cis-ADT device and the trans-ADT device can present the significant rectification, and the corresponding giant spin current rectification ratios are close to 10¹¹ and 10¹⁰ respectively. In addition, the current-voltage characteristics of two devices both perform a perfect spin filtering behavior in the positive bias region due to the huge difference between the up-spin current value and the down-spin current value. These findings are of great significance in the functional applications of spin-resolved molecular devices in the future.