Design of a Giant Magnetoresistance Device with High Spin Filter Efficiency

Molecular spintronics may boost the development of nanoscale devices with improved performance and enhanced functionality, which is very promising for the next generation of electronic devices. Here, we design a new type of spintronics device based on the novel 2D material C3N. Using nonequilibrium Green’s function in combination with the density functional theory, we systematically study the spin-dependent transport properties in four different magnetic configurations of the C3N junction, and the perfect spin filter efficiency and giant magnetoresistance effects are achieved. The calculated results clearly demonstrate that the transport properties of the C3N junction are sensitive to the magnetic configuration of the electrodes. The calculated spin-resolved transmission spectra of the proposed ferromagnetic coupling C3N junctions exhibit a robust spin filtering effect, where the conductance is mainly governed by the spin-down electrons. Under the small bias voltage, the transport properties are mainly determined by the spin-down channel and exhibit a large spin polarization. The conductance of three antiferromagnetic coupling states is nearly zero at the Fermi level. These theoretical results indicate that the novel 2D C3N monolayer is promising for molecular spintronics devices in the near future.