Ferroelectric-controlled magnetoelectric effect at the CrI3/HfO2 interface

This is the authors' abstract. We don't add key points for this paper.

The effective manipulation magnetic properties of two-dimensional magnets through electric field presents profound implications for spintronics. In this study, we investigate the ferroelectric-controlled magnetoelectric coupling within the CrI₃/HfO₂(111)/CrI₃ heterostructure by using first-principles calculations. It is found that the magnetic moments of CrI₃ are notably responsive to the polarization orientation---either directed towards (Pᵢₙ) or away (Pₒᵤₜ) from the interface. The polarization of HfO₂ triggers the accumulation (depletion) of screening electrons at the Pᵢₙ (Pₒᵤₜ) interface, which affects the relative population of the exchange-split spin bands at the interface and thus results in the enhanced (reduced) total magnetic moments of the monolayer CrI₃. The easy magnetization axis of CrI₃ switches from an out-of-plane (Pₒᵤₜ state) to an in-plane (Pᵢₙ state) direction by the reversal of ferroelectric polarization of HfO₂. Additionally, the Curie temperature (TC) of monolayer CrI₃ is enhanced by 78% in the Pₒᵤₜ state. This work provides useful guidelines for the study of interfacial magnetoelectric coupling and design of multiferroic devices.