A team of researchers has demonstrated that monolayer chromium triiodide (CrI₃) exhibits Ising ferromagnetism with out-of-plane spin orientation, showing that intrinsic magnetism can exist in two-dimensional (2D) materials. The study, conducted using magneto-optical Kerr effect (MOKE) microscopy, reveals that monolayer CrI₃ has a Curie temperature of 45 K, slightly lower than the 61 K of the bulk crystal, indicating weak interlayer coupling. The research also shows that the magnetic properties of CrI₃ depend on the number of layers, with monolayer CrI₃ displaying ferromagnetism, bilayer CrI₃ showing antiferromagnetism, and trilayer CrI₃ reverting to ferromagnetism. This layer-dependent magnetic behavior highlights the unique properties of van der Waals crystals, where physical properties can vary significantly with thickness. The findings suggest that atomically-thin materials can be used to study magnetism, with potential applications in magnetoelectronics and novel interface phenomena. The study also demonstrates that the magnetic ground state of CrI₃ has zero out-of-plane magnetization, and that the magnetic behavior is influenced by interlayer coupling, which can be either ferromagnetic or antiferromagnetic. The results provide new insights into the magnetic properties of 2D materials and open up opportunities for exploring quantum phenomena in novel hybrid superconducting systems.A team of researchers has demonstrated that monolayer chromium triiodide (CrI₃) exhibits Ising ferromagnetism with out-of-plane spin orientation, showing that intrinsic magnetism can exist in two-dimensional (2D) materials. The study, conducted using magneto-optical Kerr effect (MOKE) microscopy, reveals that monolayer CrI₃ has a Curie temperature of 45 K, slightly lower than the 61 K of the bulk crystal, indicating weak interlayer coupling. The research also shows that the magnetic properties of CrI₃ depend on the number of layers, with monolayer CrI₃ displaying ferromagnetism, bilayer CrI₃ showing antiferromagnetism, and trilayer CrI₃ reverting to ferromagnetism. This layer-dependent magnetic behavior highlights the unique properties of van der Waals crystals, where physical properties can vary significantly with thickness. The findings suggest that atomically-thin materials can be used to study magnetism, with potential applications in magnetoelectronics and novel interface phenomena. The study also demonstrates that the magnetic ground state of CrI₃ has zero out-of-plane magnetization, and that the magnetic behavior is influenced by interlayer coupling, which can be either ferromagnetic or antiferromagnetic. The results provide new insights into the magnetic properties of 2D materials and open up opportunities for exploring quantum phenomena in novel hybrid superconducting systems.