Coexisting Magnetism, Ferroelectric, and Ferrovalley Multiferroic in Stacking-Dependent Two-Dimensional Materials

Abstract

Two-dimensional (2D) multiferroic materials have widespread application prospects in facilitating the integration and miniaturization of nanodevices. However, the magnetic, ferroelectric, and ferrovalley properties in one 2D material are rarely coupled. Here, we propose a mechanism for manipulating magnetism, ferroelectric, and valley polarization by interlayer sliding in a 2D bilayer material. Monolayer GdI 2 is a ferromagnetic semiconductor with a valley polarization of up to 155.5 meV. More interestingly, the magnetism and valley polarization of bilayer GdI 2 can be strongly coupled by sliding ferroelectricity, making these tunable and reversible. In addition, we uncover the microscopic mechanism of the magnetic phase transition by a spin Hamiltonian and electron hopping between layers. Our findings offer a new direction for investigating 2D multiferroic devices with implications for next-generation electronic, valleytronic, and spintronic devices.

Layer-Dependent Quantum Anomalous Hall and Quantum Spin Hall Effects in Two-Dimensional LiFeTe

“…By contrast, the magnetic transition temperature of multilayer Cr 2 Sn 2 Te 6 is higher in thicker films . Meanwhile, the effect of layer dependence is also presented in ferrovalley material. − It is found that the valley polarization can be simultaneously regulated by electric and magnetic fields in bilayer-stacked ferrovalley materials. , The above research results clearly manifest that novel physical phenomena could be expected in 2D materials by regulating their stacking thickness.…”

Antiferromagnetism in GaS monolayer doped with TM–TM atom pairs (TM = V, Cr, Mn, and Fe)

“…So far, a large variety of 2D materials beyond graphene and its derivatives have been fabricated, thanks to the advanced synthesis method, such as those of the IVA group (silicene, 3 germanene, 4 stanene, 5 and silicon carbide 6 ), the VA group or pnictogens (phosphorene, 7,8 arsenene, 9 and antimonene 10 ), hexagonal boron nitride (h-BN), 11,12 and transition-metal dichalcogenides (MX 2 , where M = Mo and W, X = S and Se), 13–16 among others. In this regard, intriguing properties, such as ferrovalley, 17,18 topological bands, 19 multiferroic, 20 and more, have been found. Investigations have explored 2D materials as potential candidates for light-emitting devices, 21,22 gas sensing, 23,24 catalysis, 25,26 photonics, 27,28 and energy production and storage, 29,30 among others.…”