Search

Ferromagnetic order in two-dimensional (2D) van der Waals crystals has been attracting much attention recently. Remarkably, room temperature metallic ferromagnetism is realized in 2D Fe3GeTe2. Here we design a monolayer (ML) Fe3GeTe2 spin-valve device by attaching two ends to ferromagnetic electrodes and applying a magnetic field to these ferromagnetic electrodes. We investigate the spin-involved transport characteristics of such a spin valve by using ab initio quantum transport simulation. A high magnetoresistance of ∼390% is obtained and significantly increased to 450–510% after the gates are introduced. The magnetoresistance of the ML Fe3GeTe2 spin valve is insensitive to the strain modulation. Our study provides a potential option for magnetic storage applications and will motivate further studies in spintronics based on this class of materials. [ABSTRACT FROM AUTHOR]

The scarcity of two-dimensional (2D) magnetic nanostructures has hindered their applications in spintronics, which is attributed to that most magnetic materials exhibit non-van der Waals (nvdWs) structures and it is hard to reduce their thickness to 2D nanostructures. Thus it is necessary to develop a promising strategy for free-standing 2D magnetic nvdWs nanostructures. We have achieved free-standing 2D nvdWs hexagonal FeSe with a thickness of 2.9 nm by the reaction between the oleylamine-Se complex and Fe 2+ with the assistance of Cl - , where the synergetic effects of Cl - and -NH 2 lead to anisotropic growth. Inspiringly, the 2D hexagonal FeSe exhibits intrinsic antiferromagnetic order rooted in Fe 2+ and semiconducting nature. In addition, the temperature variation would result in the chemical environment changes of Fe 2+ , responsible for the temperature-dependent magnetic transitions. This work promotes the potential applications of 2D hexagonal FeSe and the preparation of other 2D nvdWs materials., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Ferromagnetic order in two-dimensional (2D) van der Waals crystals has been attracting much attention recently. Remarkably, room temperature metallic ferromagnetism is realized in 2D Fe3GeTe2. Here we design a monolayer (ML) Fe3GeTe2 spin-valve device by attaching two ends to ferromagnetic electrodes and applying a magnetic field to these ferromagnetic electrodes. We investigate the spin-involved transport characteristics of such a spin valve by using ab initio quantum transport simulation. A high magnetoresistance of ∼390% is obtained and significantly increased to 450-510% after the gates are introduced. The magnetoresistance of the ML Fe3GeTe2 spin valve is insensitive to the strain modulation. Our study provides a potential option for magnetic storage applications and will motivate further studies in spintronics based on this class of materials.