Independent Electrical Control of Spin and Valley Degrees in 2D Breathing Kagome Ta3I8 with Intrinsic Triferroicity

Independent electrical control of spin and valley degrees of freedom (DOFs) in 2D materials is difficult due to the coupling of spin and valley DOFs. Here we propose that spin-filter transport and valley polarization can be independently manipulated by an electric field in 2D breathing kagome Ta₃I₈ due to the possession of both triferroic (ferromagnetism, ferroelectric, and ferrovalley) and bipolar magnetic semiconducting characteristics. The spin-filter transport can be realized by applying a bias voltage without altering the semiconducting characteristic. The flip of valley polarization is fulfilled by switching the ferroelectric polarization with a gate voltage. Our results demonstrate the potential to control different DOFs independently by adjusting the direction of the electric field.