Simulating Spin Dynamic Of Magnetic Heterojunctions

With the development of science and technology,people have changed their target from focusing on the electrons' charge property to its spin property,which has brought a brand-new subject-spintronics.Spintronics considers both two properties,makes breakthroughs on the basis of the traditional technology.Scientists use the property of spin to assist or replace the original electrical devices,such as spin nano oscillator,magnetic memory,etc.In 1988,the discovery of GMR effect has dramatically promoted the development of spintronics,and pushed the commercialization of it.In the past decades,the storage space of hard disks has been expanded for many times while the speed of reading and writing also has been increased.It has been applied in many fields and achieved great success.In the follow-up research,breakthroughs have been made in many fields,including tunneling magnetoresistance,spin moment effect,spin orbital moment,two-dimensional electronic materials,topological insulators and other important findings Commercial conversion proceeds at the same time.Successful commercial applications can be seen in the production of STT-MRAM,updating the production of semiconductor deviceThis paper focuses on the spin nano oscillator.We will start from spin dynamics model(LLG equation),and then use the spin moment to analyze and calculate it.We will also consider the influence of short-wavelength magnon excitations and introduce BBS model to calculate the feasibility of spin nano oscillator in FM/NM/FM structure and its performance.At the same time,we compare and analyze the operation structure of LLGS equation and BBS equation.In the research,both of them have obtained stable precession,which can guide the design of spin microwave oscillator.In the further research,we use synthetic antiferromagnetic structure to substitute the original sandwich structure.Within this structure,we use BBS model with RKKY interaction to get THz oscillation.We find current,magnetic layer thickness and RKKY interaction intensity have effects on microwave frequency and output power and our research provides a new idea for making THz spintronics devices.