An effective regulation of the magnetism and interface of ferromagnetic materials is not only of great scientific significance,but also has an urgent need in modern industry.In this work,by using the first-principles ...An effective regulation of the magnetism and interface of ferromagnetic materials is not only of great scientific significance,but also has an urgent need in modern industry.In this work,by using the first-principles calculations,we demonstrate an effective approach to achieve non-volatile electrical control of ferromagnets,which proves this idea in multiferroic heterostructures of ferromagnetic La TiO_(3)and ferroelectric Bi FeO_(3).The results show that the magnetic properties and two-dimensional electron gas concentrations of La TiO_(3)films can be controlled by changing the polarization directions of Bi FeO_(3).The destroyed symmetry being introduced by ferroelectric polarization of the system leads to the transfer and reconstruction of the Ti-3 d electrons,which is the fundamental reason for the changing of magnetic properties.This multiferroic heterostructures will pave the way for non-volatile electrical control of ferromagnets and have potential applications.展开更多
Two-dimensional （2D） equations for multiferroic （MF） laminated plates with imperfect interfaces are established in this paper. The interface between two adjacent sublayers, which are not perfectly bonded together,...Two-dimensional （2D） equations for multiferroic （MF） laminated plates with imperfect interfaces are established in this paper. The interface between two adjacent sublayers, which are not perfectly bonded together, is modeled as a general spring-type layer. The mechanical displacements, and the electric and magnetic potentials of the two adjacent layers are assumed to be discontinuous at the interface. As an example, the influences of imperfect interfaces on the magnetoelectric （ME） coupling effects in an MF sandwich plate are investigated with the established 2D governing equations. Numerical results show that the imperfect interfaces have a significant impact on the ME coupling effects in MF laminated structures.展开更多
In this study, we observe a strong inverse magnetoelectric coupling in Fe52.5Co22.5B25.0/PZN-PT multiferroic heterostructure, which produces large electric field（E-field） tunability of microwave magnetic properties....In this study, we observe a strong inverse magnetoelectric coupling in Fe52.5Co22.5B25.0/PZN-PT multiferroic heterostructure, which produces large electric field（E-field） tunability of microwave magnetic properties. With the increase of the E-field from 0 to 8 kV/cm, the magnetic anisotropy field Heffis dramatically enhanced from 169 to 600 Oe, which further leads to a significant enhancement of ferromagnetic resonance frequency from 4.57 to 8.73 GHz under zero bias magnetic field, and a simultaneous decrease of the damping constant α from 0.021 to 0.0186. These features demonstrate that this multiferroic composite is a promising candidate for fabricating E-field tunable microwave components.展开更多
Realizing robust magnetoelectric(ME)coupling effect near room temperature is still a long-standing challenge for the application of multiferroic materials in next-generation low-power spintronic and memory devices.Her...Realizing robust magnetoelectric(ME)coupling effect near room temperature is still a long-standing challenge for the application of multiferroic materials in next-generation low-power spintronic and memory devices.Here we report a systematic study on the magnetic,dielectric,and ME coupling properties of Y-type hexaferrite Ba_(0.5)Sr_(1.5)Co_(2)Fe_(12-x)Al_(x)O_(22)(x=0.0,0.5,1.0)single crystals.The Al doping can induce the shifting of the alternating longitudinal conical(ALC)-proper screw(PS)magnetic phase transition temperature from 200 K for x?0e365 K for x-1.0.The most interesting feature is that the Ba_(0.5)Sr_(1.5)Co_(2)Fe_(11)AlO_(22) single crystal displays a direct and converse ME coupling coefficient with aH~3,100 ps/m and aE~3,900 ps/m at 250 K,respectively,due to the Al-doped enhanced stability of ALC phase.Moreover,the exchange bias also verifies the strong coupling of electric and magnetic orders.These results provide a valuable insight on the modulation of ALC structure and the mechanism of ME effect in Y-type hexaferrites.展开更多
基金the National Natural Science Foundation of China(Grant No.12047517)the International Cooperation Project of Science and Technology of Henan Province,China(Grant No.182102410096)+1 种基金the Natural Science Foundation of Henan Province,China(Grant No.202300410069)the China Postdoctoral Science Foundation(Grant Nos.2020M682274 and 2020TQ0089)。
文摘An effective regulation of the magnetism and interface of ferromagnetic materials is not only of great scientific significance,but also has an urgent need in modern industry.In this work,by using the first-principles calculations,we demonstrate an effective approach to achieve non-volatile electrical control of ferromagnets,which proves this idea in multiferroic heterostructures of ferromagnetic La TiO_(3)and ferroelectric Bi FeO_(3).The results show that the magnetic properties and two-dimensional electron gas concentrations of La TiO_(3)films can be controlled by changing the polarization directions of Bi FeO_(3).The destroyed symmetry being introduced by ferroelectric polarization of the system leads to the transfer and reconstruction of the Ti-3 d electrons,which is the fundamental reason for the changing of magnetic properties.This multiferroic heterostructures will pave the way for non-volatile electrical control of ferromagnets and have potential applications.
基金supported by the National Natural Science Foundation of China(11672265,11202182,11272281,11621062,and 11321202)the Fundamental Research Funds for the Central Universities(2016QNA4026 and 2016XZZX001-05)the open foundation of Zhejiang Provincial Top Key Discipline of Mechanical Engineering
文摘Two-dimensional （2D） equations for multiferroic （MF） laminated plates with imperfect interfaces are established in this paper. The interface between two adjacent sublayers, which are not perfectly bonded together, is modeled as a general spring-type layer. The mechanical displacements, and the electric and magnetic potentials of the two adjacent layers are assumed to be discontinuous at the interface. As an example, the influences of imperfect interfaces on the magnetoelectric （ME） coupling effects in an MF sandwich plate are investigated with the established 2D governing equations. Numerical results show that the imperfect interfaces have a significant impact on the ME coupling effects in MF laminated structures.
基金Project supported by the National Natural Science Foundation of China(Grant No.11674187)
文摘In this study, we observe a strong inverse magnetoelectric coupling in Fe52.5Co22.5B25.0/PZN-PT multiferroic heterostructure, which produces large electric field（E-field） tunability of microwave magnetic properties. With the increase of the E-field from 0 to 8 kV/cm, the magnetic anisotropy field Heffis dramatically enhanced from 169 to 600 Oe, which further leads to a significant enhancement of ferromagnetic resonance frequency from 4.57 to 8.73 GHz under zero bias magnetic field, and a simultaneous decrease of the damping constant α from 0.021 to 0.0186. These features demonstrate that this multiferroic composite is a promising candidate for fabricating E-field tunable microwave components.
基金supported by the National Key Research Program of China(2022YFB3807603)the Science and Technology Projects in Guangzhou(202201000008)+2 种基金the Guangdong Provincial Key Laboratory(2020B1212060066)the National Natural Science Foundation of China(Grants Nos.52272108,and 52002134)the Hubei Provincial Natural Science Foundation of China(2023AFA105).
文摘Realizing robust magnetoelectric(ME)coupling effect near room temperature is still a long-standing challenge for the application of multiferroic materials in next-generation low-power spintronic and memory devices.Here we report a systematic study on the magnetic,dielectric,and ME coupling properties of Y-type hexaferrite Ba_(0.5)Sr_(1.5)Co_(2)Fe_(12-x)Al_(x)O_(22)(x=0.0,0.5,1.0)single crystals.The Al doping can induce the shifting of the alternating longitudinal conical(ALC)-proper screw(PS)magnetic phase transition temperature from 200 K for x?0e365 K for x-1.0.The most interesting feature is that the Ba_(0.5)Sr_(1.5)Co_(2)Fe_(11)AlO_(22) single crystal displays a direct and converse ME coupling coefficient with aH~3,100 ps/m and aE~3,900 ps/m at 250 K,respectively,due to the Al-doped enhanced stability of ALC phase.Moreover,the exchange bias also verifies the strong coupling of electric and magnetic orders.These results provide a valuable insight on the modulation of ALC structure and the mechanism of ME effect in Y-type hexaferrites.
