Reserch Of The Spin Transition Mechanism Of Al-Fe Co-doped 2d-SiC Under The Synergistic Effect Of Electric Field

In recent years:with the updating of semiconductor devices,the third generation semiconductor materials bave been gradually unified with the design of spin logic devices to satisfy the process requirements.Whereas,artificial means to realize the modification doping of materials can broaden the application field of non-magnetic silicon carbide substrate from the atomic level.Based on this,this paper,by means of the first principles calculation method,successively adopts single atom Fe-doped and outer field superimposed Al-Fe-co-doped intrinsic Two-dimensional SiC to conduct magnetic regulation,and analyzes its local spin and transport mechanism.The main conclusions are as follows;By introducing the impurity Fe atom and doping the two-dimensional SiC surface with non-equivalent sites(in place of Si atom,in place of C atom,in place of interstitial site),magnetic moments are locally distributed near Fe atoms,The net spin charge contributing to the magnetie moment decreases gradually along the lattice and a small amount of magnetic moment is distributed in the neighboring atoms.We found,that the system presents local spin polarization and is a semi-metallic crystal material with complete polarization in place of Si site.The narrow band on the Fermi surface indicates that the itinerant d electrons have the behavior of a small polaron,and the polarization field changes the group velocity and motion state of the wave packet,resulting in the magnetic crystal anisotropy of the system,with the magnetic moment value of 4.00?B.When Fe replaces doped C and interstitial positions,the system is a magnetic semiconductor with incomplete polarization.The spin texture of magnetic 2D-SiC indicates that the Rashba-Drsselhaus type spin orbit coupling coexists the polar state of the wave packet,resulting in the magnetic crystal anisotropy of the system,with the magnetic moment value of 4.00?B.When Fe replaces doped C and interstitial positions,the system is a magnetic semiconductor with incomplete polarization.The spin texture of magnetic 2D-SiC indicates that the Rashba-Dresselhaus type spin orbit coupling coexists in the polar system,which induces the interaction between spin and charge and excites the spin pump effect of polar materials.All these results show that Fe atomic selective doping can be used in future spin electronic devices and magnetic storage devices.The electronic band structure above indicates that the substitutional silicon doping of Fe atoms causes the complete polarization of the system,the structure performance of the excellent properties of spintronics devices.However,d electron also introduces local narrow-band effect.In order to make the system to be delocalization,we select Al atomic pair doped with two-dimensional polar SiC,and regulate the spin transport performance of the system under the effect of electric field coupling.It is found that the transition from spin to charge to spin current is effectively realized by electric field,namely inverse spin Hall effect and spin Hall effect.The spin charge and localized electron calculation show that the system exhibits super-transport characteristics when the given voltage is 0.6eV/A.The calculation of Fermi velocity shows anisotropic at different points and the ?-electron velocity is greater than the ?-electron velocity when the spin orbit coupling is taken into account or not.The calculation of spin texture shows that when the reverse electric field is applied to the system,due to the difference between the electron spin direction and the electric field direction,the low momentum spin turns over,the damping effect is enhanced,and the magnetization is weakened.However,the system under the action of positive electric field shows the enhancement of ferromagnetic sequence and the lock of spin with momentum,which is benefit the protection and reuse of multimedia information,and the interchange between electrons cause the system to present magnetic diversity.