Zero-net-magnetization hybrid magnet.

Zero-net-magnetization magnets possess ultradense and ultrafast application potential, benefiting from their intrinsic zero stray field and terahertz dynamics characteristics. Herein, we propose the concept of zero-net-magnetization hybrid magnet, in which magnetic atoms with opposite spin polarization are partially coupled via spatial inversion (P ) symmetry, partially via rotation/mirror (C/M ) symmetry or partially without any symmetry correlation. From a local perspective and neglecting the interactions between local regions, hybrid magnet can be regarded as being composed of P T -antiferromagnet (possessing the combined symmetry (P T ) of P and time-reversal (T )), altermagnet, or fully compensated ferrimagnet. To realize hybrid magnet, we propose that such system can be constructed by forming heterojunction with three types of zero-net-magnetization magnetic monolayers. We mainly investigate the heterojunction composed of two kinds of zeronet-magnetization magnets, among which one type corresponds to fully compensated ferrimagnet. When heterojunction hybrid magnet exhibits a type-II band alignment, only one of electron doping and hole doping can induce a net magnetic moment, while the other hardly generates any net magnetization. Taking the heterojunction constructed by P T -antiferromagnet and fully compensated ferrimagnet as an example, we verify our proposal by means of the tight-binding (TB) model. Finally, taking the Cr2C2S6/CrMoC2S6 heterojunction as an example, we perform first-principles calculations combined with electric field modulation to validate our TB model and theoretical proposal.