The voltage control of magnetism has attracted intensive attention owing to the abundant physical phenomena associated with magnetoelectric coupling. More importantly, the techniques to electrically manipulate spin dy...The voltage control of magnetism has attracted intensive attention owing to the abundant physical phenomena associated with magnetoelectric coupling. More importantly, the techniques to electrically manipulate spin dynamics, such as magnetic anisotropy and ferromagnetic resonance, are of great significance because of their potential applications in high-density memory devices, microwave signal processors, and magnetic sensors. Recently, voltage control of spin waves has also been demonstrated in several multiferroic heterostructures. This development provides new platforms for energyefficient, tunable magnonic devices. In this review, we focus on the most recent advances in voltage control of ferromagnetic resonance and spin waves in magnetoelectric materials and discuss the physical mechanisms and prospects for practical device applications.展开更多
Exchange bias between ferromagnetic and antiferromagnetic layers has been widely utilized in spintronic devices.Controlling the exchange bias in magnetic multilayers by an electric field(E-field)has been proposed as a...Exchange bias between ferromagnetic and antiferromagnetic layers has been widely utilized in spintronic devices.Controlling the exchange bias in magnetic multilayers by an electric field(E-field)has been proposed as a low-power solution for manipulating the macroscopic properties such as exchange bias fields and magnetization values,while how the magnetic domains respond to the E-fields has rarely been reported in an exchange-biased system.Here,we realize the vector imaging of reversible electrical modulation of magnetization reversal in exchange-biased CoFeB/IrMn/PMN-PT(011)multiferroic heterostructures,utilizing in-situ quantitative magneto-optical Kerr effect(MOKE)microscopy.Under the electrical control,magnetic domains at-80 Oe rotate reversibly between around 160°and 80°-120°,whose transverse components reverse from 225°to 45°correspondingly.Moreover,pixel-by-pixel comparisons are conducted to further imply the reversible magnetization reversal by E-fields.Efield-induced reversible magnetization reversal is also demonstrated without applying external magnetic fields.Vector imaging of electrical manipulation of exchange bias is of great significance in understanding the magnetoelectric effect and the development of next-generation spintronic devices.展开更多
Electric field(E-field)control of magnetism based on magnetoelectric coupling is one of the promising approaches for manipulating the magnetization with low power consumption.The evolution of magnetic domains under in...Electric field(E-field)control of magnetism based on magnetoelectric coupling is one of the promising approaches for manipulating the magnetization with low power consumption.The evolution of magnetic domains under in-situ E-fields is significant for the practical applications in integrated micro/nano devices.Here,we report the vector analysis of the E-field-driven antiparallel magnetic domain evolution in FeCoSiB/PMN-PT(011)multiferroic heterostructures via in-situ quantitative magneto-optical Kerr microscope.It is demonstrated that the magnetic domains can be switched to both the 0°and 180°easy directions at the same time by E-fields,resulting in antiparallel magnetization distribution in ferromagnetic/ferroelectric heterostructures.This antiparallel magnetic domain evolution is attributed to energy minimization with the uniaxial strains by E-fields which can induce the rotation of domains no more than 90°.Moreover,domains can be driven along only one or both easy axis directions by reasonably selecting the initial magnetic domain distribution.The vector analysis of magnetic domain evolution can provide visual insights into the strain-mediated magnetoelectric effect,and promote the fundamental understanding of electrical regulation of magnetism.展开更多
Piezoelectric ceramics exhibit three conventional piezoelectric coefficients,i.e.,d33,d31,d15,due to their∞mm crystal symmetry.Unconventional piezoelectric coefficients,such as d11,d12,d13,d14,d16,etc.,can only be ex...Piezoelectric ceramics exhibit three conventional piezoelectric coefficients,i.e.,d33,d31,d15,due to their∞mm crystal symmetry.Unconventional piezoelectric coefficients,such as d11,d12,d13,d14,d16,etc.,can only be extracted from piezoelectric single crystals of special symmetry with specific cut direction.Here we demonstrate a rotated poling method to realize unconventional piezoelectric coefficients in perovskite piezoelectric ceramics.This method is elaborated in theory and experimentally proven to be effective.Full nonzero piezoelectric coefficients in the 36 piezoelectric coefficients matrix can be obtained by combining these“quasi(effective)piezoelectric coefficients”with the conventional piezoelectric coefficients,which would expand applications in a wide variety of piezoelectric devices.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.51602244)the National 111 Project of China(Grant No.B14040)the Fundamental Research Funds for the Central Universities,China(Grant No.xjj2018207)
文摘The voltage control of magnetism has attracted intensive attention owing to the abundant physical phenomena associated with magnetoelectric coupling. More importantly, the techniques to electrically manipulate spin dynamics, such as magnetic anisotropy and ferromagnetic resonance, are of great significance because of their potential applications in high-density memory devices, microwave signal processors, and magnetic sensors. Recently, voltage control of spin waves has also been demonstrated in several multiferroic heterostructures. This development provides new platforms for energyefficient, tunable magnonic devices. In this review, we focus on the most recent advances in voltage control of ferromagnetic resonance and spin waves in magnetoelectric materials and discuss the physical mechanisms and prospects for practical device applications.
基金supported by the National Key R&D Program of China(2018YFB0407601)the National Natural Science Foundation of China(91964109,62071374 and 51802248)the National 111 Project of China(B14040).
文摘Exchange bias between ferromagnetic and antiferromagnetic layers has been widely utilized in spintronic devices.Controlling the exchange bias in magnetic multilayers by an electric field(E-field)has been proposed as a low-power solution for manipulating the macroscopic properties such as exchange bias fields and magnetization values,while how the magnetic domains respond to the E-fields has rarely been reported in an exchange-biased system.Here,we realize the vector imaging of reversible electrical modulation of magnetization reversal in exchange-biased CoFeB/IrMn/PMN-PT(011)multiferroic heterostructures,utilizing in-situ quantitative magneto-optical Kerr effect(MOKE)microscopy.Under the electrical control,magnetic domains at-80 Oe rotate reversibly between around 160°and 80°-120°,whose transverse components reverse from 225°to 45°correspondingly.Moreover,pixel-by-pixel comparisons are conducted to further imply the reversible magnetization reversal by E-fields.Efield-induced reversible magnetization reversal is also demonstrated without applying external magnetic fields.Vector imaging of electrical manipulation of exchange bias is of great significance in understanding the magnetoelectric effect and the development of next-generation spintronic devices.
基金supported by the National Key R&D Program of China(Grant No.2018YFB0407601)the National Natural Science Foundation of China(Grant Nos.91964109,62071374,and 51802248)+1 种基金the National 111 Project of China(Grant No.B14040)the Fundamental Research Funds for the Central Universities(Grant No.xxj022020008).
文摘Electric field(E-field)control of magnetism based on magnetoelectric coupling is one of the promising approaches for manipulating the magnetization with low power consumption.The evolution of magnetic domains under in-situ E-fields is significant for the practical applications in integrated micro/nano devices.Here,we report the vector analysis of the E-field-driven antiparallel magnetic domain evolution in FeCoSiB/PMN-PT(011)multiferroic heterostructures via in-situ quantitative magneto-optical Kerr microscope.It is demonstrated that the magnetic domains can be switched to both the 0°and 180°easy directions at the same time by E-fields,resulting in antiparallel magnetization distribution in ferromagnetic/ferroelectric heterostructures.This antiparallel magnetic domain evolution is attributed to energy minimization with the uniaxial strains by E-fields which can induce the rotation of domains no more than 90°.Moreover,domains can be driven along only one or both easy axis directions by reasonably selecting the initial magnetic domain distribution.The vector analysis of magnetic domain evolution can provide visual insights into the strain-mediated magnetoelectric effect,and promote the fundamental understanding of electrical regulation of magnetism.
基金support by the Fundamental Research Funds for the Central Universities.This work was supported by the National Key R&D Program of China(Grant No.2018YFB0407601)the Natural Science Foundation of China(Grant Nos.91964109,51802248,and 11534015)+1 种基金China Postdoctoral Science Foundation(Grant No.2019M653605)the National 111 Project of China(B14040).
文摘Piezoelectric ceramics exhibit three conventional piezoelectric coefficients,i.e.,d33,d31,d15,due to their∞mm crystal symmetry.Unconventional piezoelectric coefficients,such as d11,d12,d13,d14,d16,etc.,can only be extracted from piezoelectric single crystals of special symmetry with specific cut direction.Here we demonstrate a rotated poling method to realize unconventional piezoelectric coefficients in perovskite piezoelectric ceramics.This method is elaborated in theory and experimentally proven to be effective.Full nonzero piezoelectric coefficients in the 36 piezoelectric coefficients matrix can be obtained by combining these“quasi(effective)piezoelectric coefficients”with the conventional piezoelectric coefficients,which would expand applications in a wide variety of piezoelectric devices.
