Engineering Electric Spin-orbit Coupling In Ferroelectric Semiconductor Heterostructure And Magnetic Metal/oxide Interface

With the development of science and technology,are required to have the advantages of miniaturization,low power consumption,however,due to the limitation of the size,power consumption through the property of electronic charge in traditional microelectronics,a new cross-disciplinary,spintronics,which is combined with the magnetism,electronics and informatics,gradually becomes one of the hottest issues in condensed matter physics.In spintronics,the spin-orbit coupling is a typical physics property in spin electronic devices In recent years,we have many research in the study of the controlling of the electron spin through interfacial field and ferroelectric field in heterostructure.It's all known that ferroelectric materials have the physical properties of ferroelectric polarization,piezoelectric,thermoelectric,et.al..Therefore,more new electronic devices can be realized in ferroelectric semiconductor.In recent years,bulk ferroelectric semiconductor,GeTe,owing to giant Rashba spin orbit coupling effect,has attracted many researchers about the studying of the spin field effect transistor based on spintronics.Meanwhile,spintronics,also can be applied to magnetic storage devices,and we can realize the controlling of the electronic spin in magnetic metal/oxide systems through the influence of interfacial filed in magnetocrystalline anisotropy.In this paper,by first principles calculation,we research the spin-orbit coupling in ferroelectric semiconductor,GeTe,and the magnetocrystalline anisotropy in magnetic metal/oxide heterostructure.The main content are as follows:1.We research the Rashba SOC in ferroelectric semiconductor superlattice GeTe?111?/InP?111?.Owing to the interfacial field,it's induced a weak Rashba splitting in bandstructure,and we obtain a large modulation of Rashba SOC by tuning the ferroelectric field and ferroelectric displacements,and we find that Rashba SOC does not monotonically increase with the increase of ferroelectric displacements.We also find that the spin polarization can be reversed by changing the ferroelectricity,in which Rashba SOC works as a bridge that connects the spin and charge degrees of freedom.2.We investigate the MAE of Fe/SrTiO₃?001?and Fe/SrTiO₃?110?,we confirm that it's effective to tailor MAE by different interfaces which lead to different bonding states and charge transfer.Compared with the Fe monolayer,the MAE of Fe/SrTiO₃?001?is decrease.On the contrary,compared with the Fe monolayer,the MAE of Fe/SrTiO₃?110?is increase.Both Fe/STO?001?and Fe/STO?110?have a strong hybridization in Fe-3d orbit and O-2p orbit.