ZrTe2/CrTe2: an epitaxial van der Waals platform for spintronics

• Published in: Nature communications Vol. 13; no. 1; p. 2972
• Main Authors: Ou, Yongxi, Yanez, Wilson, Xiao, Run, Stanley, Max, Ghosh, Supriya, Zheng, Boyang, Jiang, Wei, Huang, Yu-Sheng, Pillsbury, Timothy, Richardella, Anthony, Liu, Chaoxing, Low, Tony, Crespi, Vincent H., Mkhoyan, K. Andre, Samarth, Nitin
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 27-05-2022; Nature Publishing Group; Nature Portfolio
• Subjects: 140/146; 147/143; 147/28; 147/3; 639/766/119/1001; 639/766/119/2792; 639/766/119/997; Chemical synthesis; Electromagnetism; Epitaxial growth; Ferromagnetism; Hall effect; Heterostructures; Humanities and Social Sciences; Interfaces; Magnetic switching; Magnetism; Molecular beam epitaxy; multidisciplinary; Science; Science (multidisciplinary); Spintronics; Superconductivity; Topology; Unit cell
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-30738-1

The rapid discovery of two-dimensional (2D) van der Waals (vdW) quantum materials has led to heterostructures that integrate diverse quantum functionalities such as topological phases, magnetism, and superconductivity. In this context, the epitaxial synthesis of vdW heterostructures with well-controlled interfaces is an attractive route towards wafer-scale platforms for systematically exploring fundamental properties and fashioning proof-of-concept devices. Here, we use molecular beam epitaxy to synthesize a vdW heterostructure that interfaces two material systems of contemporary interest: a 2D ferromagnet (1T-CrTe
2
) and a topological semimetal (ZrTe
2
). We find that one unit-cell (u.c.) thick 1T-CrTe
2
grown epitaxially on ZrTe
2
is a 2D ferromagnet with a clear anomalous Hall effect. In thicker samples (12 u.c. thick CrTe
2
), the anomalous Hall effect has characteristics that may arise from real-space Berry curvature. Finally, in ultrathin CrTe
2
(3 u.c. thickness), we demonstrate current-driven magnetization switching in a full vdW topological semimetal/2D ferromagnet heterostructure device.
Van der Waals heterostructures offer the potential of integrating multiple material layers into a single device to achieve new functionalities. Here, Ou et al combine ZrTe
2
, a topological semimetal, with CrTe
2
, a 2D ferromagnet, in a single heterostructure and demonstrate spin-orbit torque switching of the 2D ferromagnet by current in the topological semimetal.