Two-dimensional magnetic tunnel p-n junctions for low-power electronics

For decades, semiconductors and their heterostructures have underpinned both fundamental and applied research across all areas of electronics. Two-dimensional, 2D (atomically thin) semiconductors have now the potential to push further the miniaturization of electronic components, enabling the development of more efficient electronics. Here, we report on a giant anomalous zero-bias spin voltage in magnetic tunnel junctions based on 2D materials. The generation, manipulation and detection of electron spin across a nanometer-thick magnetic tunnel junction do not require any applied bias. It is achieved by exploiting high-quality ferromagnetic/semiconductor interfaces and the asymmetric diffusion of spin-up/spin-down electrons across a semiconductor p-n junction. The large spin-voltage signal exceeds 30,000% and is far greater than the highest magnetoresistance signals reported to date. Our findings reveal unexplored opportunities to transform and amplify spin information for low-power electronics.