Spin Filtering and Rectification in Lateral Heterostructures of Zigzag-Edge BC₃ and Graphene Nanoribbons: Implications for Switching and Memory Devices

Heterostructures of different atomically thin nanomaterials provide an ideal platform of admixing their unique properties to achieve new functionalities. Here, we study the lateral heterostructures of graphene and BC3 nanoribbons with zigzag edge terminations within first-principles calculations. These heterostructures show localization of one kind of spin along the open graphene zigzag edge, whereas the other edge does not show any spin polarization. Therefore, the systems stabilize in the ferromagnetic ground state, inducing net magnetization and broken time reversal symmetry in each valley. Owing to this asymmetric spin distribution, the system shows spin-polarized current that is confirmed by further first-principles-based quantum transport calculations. The conduction behavior can be tuned further by changing the polarity of the side-gates in either sides of the ribbon edges. We observe higher spin polarization of current under forward gate bias but lower spin polarization of current under reverse gate bias. This functionality provides a unique way of spin filtering and rectification by changing the electrode polarity, which can find major applications in switching and memory storage devices.