Gate controllable fully spin-polarized and pure spin current in γ-graphyne nanoribbons†

Gate-controlled spin-dependent transport has paved the way for spintronic devices with tunable functionalities. In this study, we calculated the spin-dependent transport properties and photocurrent characteristics of a two-probe device based on a zigzag γ-graphyne nanoribbon (γ-GYNR), controlled by gate voltage. We found that adjusting the gate voltage polarity effectively regulated the conduction and blocking of electrons with different spin components. When the gate voltage applied to both leads is positive, a fully spin-polarized current is generated. Furthermore, we observed that a pure spin current and a fully spin-polarized photocurrent could be generated based on the photogalvanic effect. This was explained via the system's symmetry analysis. Our findings indicate an expanded application potential for the zigzag γ-GYNR in generating highly spin-polarized currents. The results highlight not only the unique spin-dependent transport and photocurrent properties of the zigzag γ-GYNR but also its potential for gate-controlled tuning. This research provides a theoretical basis for developing novel γ-GYNR-based spintronic devices, potentially leading to breakthroughs in information storage, quantum computing, and other technologies.