2D Magnetic Fe0.75Ta0.5S2: Giant Exchange Bias with Broadband Photoresponse

Abstract Understanding the interplay between magnetic and optoelectronic properties and developing spin‐optoelectronic devices are promising research strategies to further study 2D materials and advance their applications. Here, the broadband photoresponse in the newly synthesized magnetic Fe 0.75 Ta 0.5 S 2 single crystals is reported. Because the uncompensated magnetic moment of the spin glass state is pinned by the moment of the antiferromagnetic state, a large exchange bias field of ≈1.98 T is found at 2 K when cooled down at a field of 7 T. The as‐prepared samples show a large negative magnetoresistance (nMR). The field dependence of nMRs displays a similar trend up to 50 K, which is likely to originate from the significant dependence of the localization length on magnetic field. In addition, a photodetector prepared using Fe 0.75 Ta 0.5 S 2 flakes exhibits a fast response time (121.7 ms), good stability, high responsivity of 26.1 A W −1 , and broadband photodetection, showing application potentials in spin‐optoelectronics.