摘要
A grand challenge in the field of magnetism is to find material systems that exhibit spin structures ranging from simple ferromagnets to exquisite non-collinear states.In bulk three-dimensional(3D)materials,however,the magnetic exchange interactions are constrained by the crystal symmetry and quantum chemistry,making it challenging to adjust the intrinsic magnetic structure.A
A grand challenge in the field of magnetism is to find material systems that exhibit spin structures ranging from simple ferromag- nets to exquisite non-collinear states. In bulk three-dimensional （3D） materials, however, the magnetic exchange interactions are constrained by the crystal symmetry and quantum chemistry, mak- ing it challenging to adjust the intrinsic magnetic structure. A major advance for the custom-design of spin structures was the discovery that the exchange interaction can be fine-tuned in nanoscale thin film multilayers to produce either ferromagnetic （FM） or antiferro- magnetic （AF） interactions. This effect, known as interlayer exchange coupling （IEC）, is adjustable using a thin nonmagnetic spacer layer interleaved between two magnetic layers. The first indisputable experimental evidence of this magnetic coupling was demonstrated in the 1980＇s using metallic Fe/Cr and rare-earth based multilayers [1]. The ability to engineer the exchange interac- tion introduced an unprecedented level of control to produce nanostructures known as synthetic antiferromagnets （Fig. 1）. Ulti- mately, this led to the discovery of novel transport and spintronic phenomena culminating in the 2007 Nobel Prize （https：//www.no- belprize.org/nobel_prizes/physics/laureates/2007）.
