@article{
doi:10.1073/pnas.2115939119,
author = {Yucheng Jiang  and Anpeng He  and Kai Luo  and Jinlei Zhang  and Guozhen Liu  and Run Zhao  and Qing Zhang  and Zhuo Wang  and Chen Zhao  and Lin Wang  and Yaping Qi  and Ju Gao  and Kian Ping Loh  and Andrew T. S. Wee  and Cheng-Wei Qiu },
title = {Giant bipolar unidirectional photomagnetoresistance},
journal = {Proceedings of the National Academy of Sciences},
volume = {119},
number = {27},
pages = {e2115939119},
year = {2022},
doi = {10.1073/pnas.2115939119},
URL = {https://www.pnas.org/doi/abs/10.1073/pnas.2115939119},
eprint = {https://www.pnas.org/doi/pdf/10.1073/pnas.2115939119},
abstract = {Positive magnetoresistance (PMR) and negative magnetoresistance (NMR)\ describe two opposite responses of resistance induced by a magnetic field. Materials with giant PMR are usually distinct from those with giant NMR due to different physical natures. Here, we report the unusual photomagnetoresistance in the van der Waals heterojunctions of WSe2/quasi-two-dimensional electron gas, showing the coexistence of giant PMR and giant NMR. The PMR and NMR reach 1,007.5\% at –9 T and –93.5\% at 2.2 T in a single device, respectively. The magnetoresistance spans over two orders of magnitude on inversion of field direction, implying a giant unidirectional magnetoresistance (UMR). By adjusting the thickness of the WSe2 layer, we achieve the maxima of PMR and NMR, which are 4,900,000\% and –99.8\%, respectively. The unique magnetooptical transport shows the unity of giant UMR, PMR, and NMR, referred to as giant bipolar unidirectional photomagnetoresistance. These features originate from strong out-of-plane spin splitting, magnetic field–enhanced recombination of photocarriers, and the Zeeman effect through our experimental and theoretical investigations. This work offers directions for high-performance light-tunable spintronic devices.NMR)\ }}