Half-Metallic Antiferromagnetic\n2D Nonlayered Cr<sub>2</sub>Se<sub>3</sub> Nanosheets

Half-metallic magnetism, characterized by metallic behavior\nin\none spin direction and semiconducting or insulating behavior in the\nopposite spin direction, is an intriguing and highly useful physical\nproperty for advanced spintronics because it allows for the complete\nrealization of 100% spin-polarized current. Particularly, half-metallic\nantiferromagnetism is recognized as an excellent candidate for the\ndevelopment of highly efficient spintronic devices due to its zero\nnet magnetic moment combined with 100% spin polarization, which results\nin lower energy losses and eliminates stray magnetic fields compared\nto half-metallic ferromagnets. However, the synthesis and characterization\nof half-metallic antiferromagnets have not been reported until now\nas the theoretically proposed materials require a delicate and challenging\napproach to fabricate such complex compounds. Here, we propose Cr<sub>2</sub>Se<sub>3</sub> as the experimentally synthesizable half-metallic\nantiferromagnet. Our experimental and theoretical studiesincluding\nmagnetic property measurements, spin-resolved density functional theory\ncalculations, and tunneling magnetoresistance experimentsconfirm\nits half-metallic antiferromagnetic behavior. We demonstrate that\nthe 2D nonlayered Cr<sub>2</sub>Se<sub>3</sub> synthesized via chemical\nvapor deposition offers an ideal platform for innovative spintronics\napplications and fundamental research into half-metallic antiferromagnets.