Voltage Control of Magnetism in Fe_3-xGeTe₂/In₂Se₃ van der Waals Heterostructures

We investigate the electronic and magnetic properties of ferromagnetic/ferroelectric in Fe_3-xGeTe₂/In₂Se₃heterostructures. It is observed that gate voltages applied to the Fe₃xGeTe2/In2Se3 heterostructure device modulate the magnetic properties of Fe3-xGeTe2 with a significant decrease in the coercive field for both positive and negative voltages. Raman spectroscopy on the heterostructure device shows a voltage-dependent increase in the in-plane In₂Se₃ and Fe_3-xGeTe₂ lattice constants for both voltage polarities. Thus, the voltage-dependent decrease in the Fe_3-xGeTe₂ coercive field, regardless of the gate voltage polarity, can be attributed to the in-plane tensile strain. This is supported by density functional theory calculations showing tensile-strain-induced reduction of the magnetocrystalline anisotropy, which in turn decreases the coercive field. Our results demonstrate an effective method to realize low-power voltage-controlled vdW spintronic devices utilizing the magnetoelectric effect in van der Waals ferromagnetic/ferroelectric heterostructures.<br/><br/>This work is supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (No. RS-2024-00358551) and by the Ministry of Education (Nos. 2021R1A6A1A03043957 and 2021R1A6A1A10044154).