Integrating semiconducting and magnetic materials could combine transistor-like operation with nonvolatility and enable architectures such as logic-in-memory. Here, we employ correlated electrical transport and scanning nitrogen-vacancy (NV) center magnetic imaging to elucidate a spin transistor concept that amalgamates both vertical and lateral transport in a 2D antiferromagnetic semiconductor, distinct from purely vertical tunneling devices. Our device, based on a monolayer-bilayer junction in CrSBr, displays giant, gate-tunable magnetoresistance driven by the dual action of electrostatic doping on space-charge-limited lateral conduction and interlayer exchange coupling. Moreover, we visualize a field-trainable, layer-sharing effect that selects between coherent or domain-wall reversal at the spin-flip transition, enabling multilevel, memristive conductance states. These findings open opportunities for 2D magnetic semiconductors to address limitations in contemporary computing.
@article{arxiv.2512.03306,
title = {A Space-Charge-Limited van der Waals Spin Transistor},
author = {Thomas K. M. Graham and Yu-Xuan Wang and Niranjana Renjith Nair and Kseniia Mosina and Kenji Watanabe and Takashi Taniguchi and Zdenek Sofer and Brian B. Zhou},
journal= {arXiv preprint arXiv:2512.03306},
year = {2025}
}