Modulation of the spin transport properties of γ-graphyne by chemical anchoring groups and strain

Abstract

Abstract Chemical anchoring groups can modulate the connection between metal electrode surfaces and central molecules and regulate the distribution of electronic states and charge transport in monomolecular device energy levels. Thus, the introduction of different anchoring groups inevitably has an influence on multifunctional molecular devices. Moreover, the strain effect is also an important method for electronic property modulation of two-dimensional materials. Therefore, in this paper, three different chemical anchoring groups are combined with compressive and tensile strains, aiming for dual-modulation behavior in the spin-resolved transport properties of γ-graphyne molecular devices. Our calculation results suggest that the chemical anchoring groups of pyrrole (C4H5N), thiophene (C4H4S), and 1H-phosphole (C4H5P) molecules combined with strain have a good regulatory effect on the transport of designed molecular devices, which can be seen from the transmission spectra and molecular energy spectrum. In addition, the dual modulation can induce the spin-polarization phenomenon and the maximum spin filtering efficiency reaches 90%. Furthermore, negative differential resistance behavior has been achieved in the proposed device, and the maximum peak-to-valley ratio can reach 12.14. Our findings may provide a theoretical basis for the dual modulation of molecular junctions by chemical anchoring groups and strain for future nanoelectronic devices.