Metamagnetic transition and meta-stable magnetic state in Co-doped FeGaTe.

The transition between the ferromagnetic (FM) and anti-ferromagnetic (AFM) phases in van der Waals (vdW) magnets has been extensively studied since the discovery of vdW magnets, due to the importance of both transitions within a single material. Recently, among vdW magnets, FeGaTe (FGaT) has garnered significant attention for its robust FM properties that remain stable above room temperature. Also, the FM to AFM phase transition in this material has been achieved through substitutional Co-atom doping at Fe sites.

Magnetic properties of ferromagnetic nanoparticles of FeGeTe(= 3, 5) directly exfoliated and dispersed in pure water.

FeGeTe(= 3, 5) are two-dimensional ferromagnetic (FM) materials that have gained significant attention from researchers due to their relatively high Curie temperature and tunability. However, the methods for preparing FM nanoparticles (FNPs) and large-area FeGeTefilms are still in the early stages. Here, we studied the magnetic properties of FeGeTeFNPs exfoliated via wet exfoliation in pure water.

Unusual Dzyaloshinskii-Moriya Interaction in Graphene/FeGeTe Van der Waals Heterostructure.

Dzyaloshinskii-Moriya interaction (DMI) is shown to induce a topologically protected chiral spin texture in magnetic/nonmagnetic heterostructures. In the context of van der Waals spintronic devices, graphene emerges as an excellent candidate material. However, due to its negligible spin-orbit interaction, inducing DMI to stabilize topological spins when coupled to 3d-ferromagnets remains challenging.

Giant coercivity enhancement in a room-temperature van der Waals magnet through substitutional metal-doping.

FeGeTe ( = 3, 4, and 5) systems, two-dimensional (2D) van der Waals (vdW) ferromagnetic (FM) metals with high Curie temperatures (), have been intensively studied to realize all-2D spintronic devices. Recently, an intrinsic FM material FeGaTe with high (350-380 K) has been reported. As substitutional doping changes the magnetic properties of vdW magnets, it can be a powerful means for engineering the properties of magnetic materials.

Photoluminescence Path Bifurcations by Spin Flip in Two-Dimensional CrPS.

Ultrathin layered crystals of coordinated chromium(III) are promising not only as two-dimensional (2D) magnets but also as 2D near-infrared (NIR) emitters due to long-range spin correlation and efficient transition between high- and low-spin excited states of Cr ions. In this study, we report on the dual-band NIR photoluminescence (PL) of CrPS and show that its excitonic emission bifurcates into fluorescence and phosphorescence depending on thickness, temperature, and defect density. In addition to the spectral branching, the biexponential decay of PL transients, also affected by the three factors, could be well described within a three-level kinetic model for Cr(III).

Exchange Bias Effect in Ferro-/Antiferromagnetic van der Waals Heterostructures.

The recent discovery of magnetic van der Waals (vdW) materials provides a platform to answer fundamental questions on the two-dimensional (2D) limit of magnetic phenomena and applications. An important question in magnetism is the ultimate limit of the antiferromagnetic layer thickness in ferromagnetic (FM)/antiferromagnetic (AFM) heterostructures to observe the exchange bias (EB) effect, of which origin has been subject to a long-standing debate. Here, we report that the EB effect is maintained down to the atomic bilayer of AFM in the FM (FeGeTe)/AFM (CrPS) vdW heterostructure, but it vanishes at the single-layer limit.