Author(s): Zhu, WK (Zhu, Wenkai); Lin, HL (Lin, Hailong); Yan, FG (Yan, Faguang); Hu, C (Hu, Ce); Wang, ZA (Wang, Ziao); Zhao, LX (Zhao, Lixia); Deng, YC (Deng, Yongcheng); Kudrynskyi, ZR (Kudrynskyi, Zakhar R.); Zhou, T (Zhou, Tong); Kovalyuk, ZD (Kovalyuk, Zakhar D.); Zheng, YH (Zheng, Yuanhui); Patane, A (Patane, Amalia); Zutic, I (Zutic, Igor); Li, SS (Li, Shushen); Zheng, HZ (Zheng, Houzhi); Wang, KY (Wang, Kaiyou)

Source: ADVANCED MATERIALS Article Number: 2104658 DOI: 10.1002/adma.202104658 Early Access Date: OCT 2021

Abstract: 2D layered chalcogenide semiconductors have been proposed as a promising class of materials for low-dimensional electronic, optoelectronic, and spintronic devices. Here, all-2D van der Waals vertical spin-valve devices, that combine the 2D layered semiconductor InSe as a spacer with the 2D layered ferromagnetic metal Fe3GeTe2 as spin injection and detection electrodes, are reported. Two distinct transport behaviors are observed: tunneling and metallic, which are assigned to the formation of a pinhole-free tunnel barrier at the Fe3GeTe2/InSe interface and pinholes in the InSe spacer layer, respectively. For the tunneling device, a large magnetoresistance (MR) of 41% is obtained under an applied bias current of 0.1 mu A at 10 K, which is about three times larger than that of the metallic device. Moreover, the tunneling device exhibits a lower operating bias current but a more sensitive bias current dependence than the metallic device. The MR and spin polarization of both the metallic and tunneling devices decrease with increasing temperature, which can be fitted well by Bloch's law. These findings reveal the critical role of pinholes in the MR of all-2D van der Waals ferromagnet/semiconductor heterojunction devices.

Accession Number: WOS:000706595200001

PubMed ID: 34642998

ISSN: 0935-9648

eISSN: 1521-4095

Full Text: https://onlinelibrary.wiley.com/doi/10.1002/adma.202104658