In this work, we investigate the effects of interplay of spin-orbit interaction and in-plane magnetic fields on the electronic structure and spin texturing of parabolically confined quantum wire. Numerical results rev...In this work, we investigate the effects of interplay of spin-orbit interaction and in-plane magnetic fields on the electronic structure and spin texturing of parabolically confined quantum wire. Numerical results reveal that the competing effects between Rashba and Dresselhaus spin--orbit interactions and the external magnetic field lead to a complicated energy spectrum. We find that the spin texturing owing to the coupling between subbands can be modified by the strength of spin- orbit couplings as well as the magnitude and the orientation angle of the external magnetic field.展开更多
Our world is composed of various materials with different structures,where spin structures have been playing a pivotal role in spintronic devices of the contemporary information technology.Apart from conventional coll...Our world is composed of various materials with different structures,where spin structures have been playing a pivotal role in spintronic devices of the contemporary information technology.Apart from conventional collinear spin materials such as collinear ferromagnets and collinear antiferromagnetic ally coupled materials,noncollinear spintronic materials have emerged as hot spots of research attention due to exotic physical phenomena.In this review,we first introduce two types of noncollinear spin structures,i.e.,the chiral spin structure that yields real-space Berry phases and the coplanar noncollinear spin structure that could generate momentum-space Berry phases,and then move to relevant novel physical phenomena including topological Hall effect,anomalous Hall effect,multiferroic,Weyl fermions,spin-polarized current and spin Hall effect without spin-orbit coupling in these noncollinear spin systems.Afterward,we summarize and elaborate the electric-field control of the noncollinear spin structure and related physical effects,which could enable ultralow power spintronic devices in future.In the final outlook part,we emphasize the importance and possible routes for experimentally detecting the intriguing theoretically predicted spin-polarized current,verifying the spin Hall effect in the absence of spin-orbit coupling and exploring the anisotropic magnetoresistance and domain-wall-related magnetoresistance effects for noncollinear antiferromagnetic materials.展开更多
Two-dimensional ferroelectric(2D-FE)materials that characterize the spontaneous ferroelectricity down to monolayer limit and rich ferroic properties arising from FE orderings,have been extensively explored as low-dime...Two-dimensional ferroelectric(2D-FE)materials that characterize the spontaneous ferroelectricity down to monolayer limit and rich ferroic properties arising from FE orderings,have been extensively explored as low-dimensional sensor,electric and memory devices.In current work,group-IV transition metal oxide dihalide MOX_(2)(M=Zr and Hf,X=Cl,Br and I)monolayers have been identified as a new group of 2D-FE materials.Using the comprehensive first-principles calculations combined with finite temperature Monte Carlo(MC)and ab initio molecular dynamics(MD)simulations,we investigate the temperature stability of FE polarization and further uncover the unique properties associated with spontaneous ferroelectricity of MOX_(2) monolayers.In particular,ZrOI_(2) monolayer,a promising 2D-FE material with room temperature stable ferroelectricity,semiconducting electronic structure and optoelectronic response under visible light,offers an ideal material platform to investigate the coupling of intrinsic anisotropy,optical absorption selectivity and spin degree of freedom with 2D ferroelectricity.Typically,significant optical absorption anisotropy and giant linear dichroism effect are predicted for a 2D optical polarizer device based on ZrOI_(2) monolayer,where the adsorption of incident monochromatic linearly polarized light(hv=3.23 eV)along two planar directions with a nearly 100%optical selectivity can be achieved.Moreover,the spin–orbit coupling(SOC)induced spin splitting of valence band edges and out-of-plane textured spin configuration occur in ZrOI_(2) monolayer.In the meanwhile,the unidirectional spin–orbit field protected by C2v wave-vector point group can further create the persistent spin helix(PSH)state,leading to the extraordinarily long spin carrier lifetime.More importantly,the nonvolatile control of PSH state via the electric field induced polarization reversal has also been demonstrated for FE-ZrOI_(2) monolayer,which manifests as a great advantage for applications of ZrOI_(2) as the lowdimensional spin-field e展开更多
文摘In this work, we investigate the effects of interplay of spin-orbit interaction and in-plane magnetic fields on the electronic structure and spin texturing of parabolically confined quantum wire. Numerical results reveal that the competing effects between Rashba and Dresselhaus spin--orbit interactions and the external magnetic field lead to a complicated energy spectrum. We find that the spin texturing owing to the coupling between subbands can be modified by the strength of spin- orbit couplings as well as the magnitude and the orientation angle of the external magnetic field.
基金financially supported by the National Natural Science Foundation of China(Nos.51822101,51861135104,51771009 and 11704018).
文摘Our world is composed of various materials with different structures,where spin structures have been playing a pivotal role in spintronic devices of the contemporary information technology.Apart from conventional collinear spin materials such as collinear ferromagnets and collinear antiferromagnetic ally coupled materials,noncollinear spintronic materials have emerged as hot spots of research attention due to exotic physical phenomena.In this review,we first introduce two types of noncollinear spin structures,i.e.,the chiral spin structure that yields real-space Berry phases and the coplanar noncollinear spin structure that could generate momentum-space Berry phases,and then move to relevant novel physical phenomena including topological Hall effect,anomalous Hall effect,multiferroic,Weyl fermions,spin-polarized current and spin Hall effect without spin-orbit coupling in these noncollinear spin systems.Afterward,we summarize and elaborate the electric-field control of the noncollinear spin structure and related physical effects,which could enable ultralow power spintronic devices in future.In the final outlook part,we emphasize the importance and possible routes for experimentally detecting the intriguing theoretically predicted spin-polarized current,verifying the spin Hall effect in the absence of spin-orbit coupling and exploring the anisotropic magnetoresistance and domain-wall-related magnetoresistance effects for noncollinear antiferromagnetic materials.
基金Authors acknowledge the funding support from the National Science Foundation of China(No.11574244)the Fundamental Research Funds for the Central Universities(No.xzy012020004)+1 种基金supported by funding from the Natural Science Foundation of China(No.61974113)the National Key Research and Development Project(No.2018YFB2202800).The National Supercomputer Center(NSCC)in Tianjin is acknowledged for computational support.
文摘Two-dimensional ferroelectric(2D-FE)materials that characterize the spontaneous ferroelectricity down to monolayer limit and rich ferroic properties arising from FE orderings,have been extensively explored as low-dimensional sensor,electric and memory devices.In current work,group-IV transition metal oxide dihalide MOX_(2)(M=Zr and Hf,X=Cl,Br and I)monolayers have been identified as a new group of 2D-FE materials.Using the comprehensive first-principles calculations combined with finite temperature Monte Carlo(MC)and ab initio molecular dynamics(MD)simulations,we investigate the temperature stability of FE polarization and further uncover the unique properties associated with spontaneous ferroelectricity of MOX_(2) monolayers.In particular,ZrOI_(2) monolayer,a promising 2D-FE material with room temperature stable ferroelectricity,semiconducting electronic structure and optoelectronic response under visible light,offers an ideal material platform to investigate the coupling of intrinsic anisotropy,optical absorption selectivity and spin degree of freedom with 2D ferroelectricity.Typically,significant optical absorption anisotropy and giant linear dichroism effect are predicted for a 2D optical polarizer device based on ZrOI_(2) monolayer,where the adsorption of incident monochromatic linearly polarized light(hv=3.23 eV)along two planar directions with a nearly 100%optical selectivity can be achieved.Moreover,the spin–orbit coupling(SOC)induced spin splitting of valence band edges and out-of-plane textured spin configuration occur in ZrOI_(2) monolayer.In the meanwhile,the unidirectional spin–orbit field protected by C2v wave-vector point group can further create the persistent spin helix(PSH)state,leading to the extraordinarily long spin carrier lifetime.More importantly,the nonvolatile control of PSH state via the electric field induced polarization reversal has also been demonstrated for FE-ZrOI_(2) monolayer,which manifests as a great advantage for applications of ZrOI_(2) as the lowdimensional spin-field e
