The magneto-electric effect in magnetic materials has been widely investigated, but obtaining an enhanced magnetoelectric effect is challenging. In this study, tricolor superlattices composed of manganese oxides-Pr（...The magneto-electric effect in magnetic materials has been widely investigated, but obtaining an enhanced magnetoelectric effect is challenging. In this study, tricolor superlattices composed of manganese oxides-Pr（0.9）Ca（0.1）MnO3,La（0.9）Sr（0.1）MnO3, and La（0.9）Sb（0.1）MnO3-on（001）-oriented Nb：SrTiO3 substrates with broken space-inversion and timereversal symmetries are designed. Regarding the electric polarization in the hysteresis loops of the superlattices at different external magnetic fields, both coercive electric field Ec and remnant polarization intensity Pr clearly show strong magneticfield dependences. At low temperatures（〈 120 K）, a considerable magneto-electric effect in the well-defined tricolor superlattice is observed that is absent in the single compounds. Both maxima of the magneto-electric coupling coefficients ？Ec and ？Pr appear at 30 K. The magnetic dependence of the dielectric constant further supports the magneto-electric effect. Moreover, a dependence of the magneto-electric effect on the periodicity of the superlattices with various structures is observed, which indicates the importance of interfaces. Our experimental results verify previous theoretical results regarding magneto-electric interactions, thereby paving the way for the design and development of novel magneto-electric devices based on manganite ferromagnets.展开更多
The development of artificial synaptic devices that emulate synaptic activity is key to advancing the hardware implementation of neuromorphic computing.In this study,we present an optoelectronic synaptic device based ...The development of artificial synaptic devices that emulate synaptic activity is key to advancing the hardware implementation of neuromorphic computing.In this study,we present an optoelectronic synaptic device based on a NaNbO_(3)/n-GaN heterostructure,which exhibits defect-dominated carrier transport behaviors.This device effectively demonstrates typical synaptic functions,including paired-pulse facilitation,short-term memory,long-term memory,human cognitive behavior,and human visual memory,using both optical and electrical stimuli.These results highlight the potential of the NaNbO_(3)/n-GaN heterostructure for future neuromorphic systems.展开更多
Magnon,the quanta of spin wave,low energy excitation from magnetic ground state,not only carries spin angular momentum which is of crucial importance in new generation of information technology,but also serves as powe...Magnon,the quanta of spin wave,low energy excitation from magnetic ground state,not only carries spin angular momentum which is of crucial importance in new generation of information technology,but also serves as powerful probes for investigating the corresponding ground-state properties.Here,we investigate magnetic order transitions in the antiferromagnetic van der Waals insulator NiPS3 using non-local magnon transport.We observe a dimensional cross-over behavior with a critical thickness of approximately 12-14 nm.Below the threshold,the thermally activated magnon carries angular momentum that is opposite to the conventional case,corresponding to the vestigial order with higher symmetry.While above this critical thickness,where NiPS3 exhibits in-plane zigzag antiferromagnetic order with lower symmetry,the thermally activated magnon signals show anomalous high-magnetic-field responses.After the spin-flop transition,the Néel vector becomes strongly pinned near the a-axis,resulting in a flattening of the detected signals that can only be switched when the magnetic field is oriented perpendicular to the Néel vector.These findings demonstrate that magnon spin currents provide an effective means to investigate exotic orders and phase transitions in van der Waals magnetic insulators,offering new insights for both fundamental research and potential applications in spin-based technologies.展开更多
With the increasing impacts of climate change and resource depletion,dielectric capacitors,with their exceptional stability,fast charging and discharging rates,and ability to operate under more extreme conditions,are ...With the increasing impacts of climate change and resource depletion,dielectric capacitors,with their exceptional stability,fast charging and discharging rates,and ability to operate under more extreme conditions,are emerging as promising high-demand candidates for high-performance energy storage devices,distinguishing them from traditional electrochemical capacitors and batteries.However,due to the shortcomings of various dielectric ceramics(e.g.,paraelectrics(PEs),ferroelectrics(FEs),and antiferroelectrics(AFEs)),their low polarizability,low breakdown strength(BDS),and large hysteresis loss limit their standalone use in the advancement of energy storage ceramics.Therefore,synthesizing novel perovskite-based materials that exhibit high energy density,high energy efficiency,and low loss is crucial for achieving superior energy storage performance.In this review,we outline the recent development of perovskitebased ferroelectric energy storage ceramics from the perspective of combinatorial optimization for tailoring ferroelectric hysteresis loops and comprehensively discuss the properties arising from the different combinations of components.We also provide future guidelines in this realm.Therefore,the combinatorial optimization strategy in this review will open up a practical route toward the application of new high-performance ferroelectric energy storage devices.展开更多
The resistive switching(RS)mechanism of hybrid organic–inorganic perovskites has not been clearly understood until now.A switchable diode-like RS behavior in MAPbBr3 single crystals using Au(or Pt)symmetric electrode...The resistive switching(RS)mechanism of hybrid organic–inorganic perovskites has not been clearly understood until now.A switchable diode-like RS behavior in MAPbBr3 single crystals using Au(or Pt)symmetric electrodes is reported.Both the high resistance state(HRS)and low resistance state(LRS)are electrode-area dependent and light responsive.We propose an electric-fielddriven inner p–n junction accompanied by a trap-controlled space-charge-limited conduction(SCLC)conduction mechanism to explain this switchable diode-like RS behavior in MAPbBr_(3) single crystals.展开更多
Electrochemical energy storage(EES)is a key technology in global research that focuses on the efficient storage and utilization of electrical energy generated from intermittent sources.The development of EES systems w...Electrochemical energy storage(EES)is a key technology in global research that focuses on the efficient storage and utilization of electrical energy generated from intermittent sources.The development of EES systems with high energy and power densities is essential for meeting the future energy demands of electrochemical capacitors,such as capacitors,which can store electrical energy obtained from intermittent sources and enable rapid energy transfer and transformation.Electrical double-layer capacitors(EDLCs)within porous carbon materials(Fig.1(a))are commercially popular because of their excellent conductivity and relatively low cost.Despite their advantages,the complex structure of nanoporous carbon materials hinders the optimization of supercapacitor performance.Although previous research has suggested that adjusting the pore size of nanoporous carbon materials can enhance their capacitive performance,conflicting reports and the lack of a definitive correlation between capacitance and pore size remain issues[1].Understanding the relationship between the structure of carbon materials and their capacitance is crucial for designing devices with high energy densities.展开更多
Piezoelectric ceramics provide high strain and large driving forces in actuators.A large electrostrain can be realized by the introduction of point defects such as vacancies,interstitial defects,and substitution defec...Piezoelectric ceramics provide high strain and large driving forces in actuators.A large electrostrain can be realized by the introduction of point defects such as vacancies,interstitial defects,and substitution defects.With Mn doping,a significant increase in the reversible electrostrain from 0.05%to 0.17%could be achieved in potassium niobite lead-free piezoelectric ceramics.The origins of the large electrostrain were analyzed via in situ X-ray diffraction(XRD)under an electric field.The electrostrain and other typical electrical properties of the samples were measured at various temperatures,which enabled the ceramics to perform under a very wide temperature range,such as−80–130℃ for the 0.5 mol%Mn-doped sample with low dielectric loss(≤0.02).More importantly,combined with characterizations of the defect behavior by thermally stimulated depolarization current(TSDC),the failure mechanisms of electrostrain in a hightemperature environment could be revealed,which was associated with synergistic damage to the defects caused by the electric field and high temperature.The results can provide good ideas and a basis for the design of piezoelectric materials with good electrostrain stability over a wide temperature range.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61471301)
文摘The magneto-electric effect in magnetic materials has been widely investigated, but obtaining an enhanced magnetoelectric effect is challenging. In this study, tricolor superlattices composed of manganese oxides-Pr（0.9）Ca（0.1）MnO3,La（0.9）Sr（0.1）MnO3, and La（0.9）Sb（0.1）MnO3-on（001）-oriented Nb：SrTiO3 substrates with broken space-inversion and timereversal symmetries are designed. Regarding the electric polarization in the hysteresis loops of the superlattices at different external magnetic fields, both coercive electric field Ec and remnant polarization intensity Pr clearly show strong magneticfield dependences. At low temperatures（〈 120 K）, a considerable magneto-electric effect in the well-defined tricolor superlattice is observed that is absent in the single compounds. Both maxima of the magneto-electric coupling coefficients ？Ec and ？Pr appear at 30 K. The magnetic dependence of the dielectric constant further supports the magneto-electric effect. Moreover, a dependence of the magneto-electric effect on the periodicity of the superlattices with various structures is observed, which indicates the importance of interfaces. Our experimental results verify previous theoretical results regarding magneto-electric interactions, thereby paving the way for the design and development of novel magneto-electric devices based on manganite ferromagnets.
基金supported by the Shanxi Provincial Basic Research Program(No.202303021212272)support of the National Natural Science Foundation of China(No.52333009)。
文摘The development of artificial synaptic devices that emulate synaptic activity is key to advancing the hardware implementation of neuromorphic computing.In this study,we present an optoelectronic synaptic device based on a NaNbO_(3)/n-GaN heterostructure,which exhibits defect-dominated carrier transport behaviors.This device effectively demonstrates typical synaptic functions,including paired-pulse facilitation,short-term memory,long-term memory,human cognitive behavior,and human visual memory,using both optical and electrical stimuli.These results highlight the potential of the NaNbO_(3)/n-GaN heterostructure for future neuromorphic systems.
基金supported by the National Key R&D Program of China(Grant No.2024YFA1409001)the Innovation Program for Quantum Science and Technology(2021ZD0302403)+2 种基金the National Natural Science Foundation of China(Grant Nos.92265106,and 12404193)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000)the China Postdoctoral Science Foundation(Grant No.GZB20240029).
文摘Magnon,the quanta of spin wave,low energy excitation from magnetic ground state,not only carries spin angular momentum which is of crucial importance in new generation of information technology,but also serves as powerful probes for investigating the corresponding ground-state properties.Here,we investigate magnetic order transitions in the antiferromagnetic van der Waals insulator NiPS3 using non-local magnon transport.We observe a dimensional cross-over behavior with a critical thickness of approximately 12-14 nm.Below the threshold,the thermally activated magnon carries angular momentum that is opposite to the conventional case,corresponding to the vestigial order with higher symmetry.While above this critical thickness,where NiPS3 exhibits in-plane zigzag antiferromagnetic order with lower symmetry,the thermally activated magnon signals show anomalous high-magnetic-field responses.After the spin-flop transition,the Néel vector becomes strongly pinned near the a-axis,resulting in a flattening of the detected signals that can only be switched when the magnetic field is oriented perpendicular to the Néel vector.These findings demonstrate that magnon spin currents provide an effective means to investigate exotic orders and phase transitions in van der Waals magnetic insulators,offering new insights for both fundamental research and potential applications in spin-based technologies.
基金support from the National Natural Science Foundation of China(No.52202154)support from the Highperformance Computing Platform of China Agricultural University.
文摘With the increasing impacts of climate change and resource depletion,dielectric capacitors,with their exceptional stability,fast charging and discharging rates,and ability to operate under more extreme conditions,are emerging as promising high-demand candidates for high-performance energy storage devices,distinguishing them from traditional electrochemical capacitors and batteries.However,due to the shortcomings of various dielectric ceramics(e.g.,paraelectrics(PEs),ferroelectrics(FEs),and antiferroelectrics(AFEs)),their low polarizability,low breakdown strength(BDS),and large hysteresis loss limit their standalone use in the advancement of energy storage ceramics.Therefore,synthesizing novel perovskite-based materials that exhibit high energy density,high energy efficiency,and low loss is crucial for achieving superior energy storage performance.In this review,we outline the recent development of perovskitebased ferroelectric energy storage ceramics from the perspective of combinatorial optimization for tailoring ferroelectric hysteresis loops and comprehensively discuss the properties arising from the different combinations of components.We also provide future guidelines in this realm.Therefore,the combinatorial optimization strategy in this review will open up a practical route toward the application of new high-performance ferroelectric energy storage devices.
基金supported by the National Natural Science Foundation of China(Nos.11964017,51972157,11864022,and 51662028)the Natural Science Foundation of Jiangxi Province(No.20192ACB21017)。
文摘The resistive switching(RS)mechanism of hybrid organic–inorganic perovskites has not been clearly understood until now.A switchable diode-like RS behavior in MAPbBr3 single crystals using Au(or Pt)symmetric electrodes is reported.Both the high resistance state(HRS)and low resistance state(LRS)are electrode-area dependent and light responsive.We propose an electric-fielddriven inner p–n junction accompanied by a trap-controlled space-charge-limited conduction(SCLC)conduction mechanism to explain this switchable diode-like RS behavior in MAPbBr_(3) single crystals.
基金supported by the National Natural Science Foundation of China(grant numbers 22102105 and 22202037)the Fundamental Research Funds for the Central Universities(grant numbers 2412024QD014 and 2412023QD019)support from Northeast Normal University.Z.X.thanks support from grants under the seventh batch of the Jilin Province Youth Science and Technology Talent Lifting Project(grant number QT202305).
文摘Electrochemical energy storage(EES)is a key technology in global research that focuses on the efficient storage and utilization of electrical energy generated from intermittent sources.The development of EES systems with high energy and power densities is essential for meeting the future energy demands of electrochemical capacitors,such as capacitors,which can store electrical energy obtained from intermittent sources and enable rapid energy transfer and transformation.Electrical double-layer capacitors(EDLCs)within porous carbon materials(Fig.1(a))are commercially popular because of their excellent conductivity and relatively low cost.Despite their advantages,the complex structure of nanoporous carbon materials hinders the optimization of supercapacitor performance.Although previous research has suggested that adjusting the pore size of nanoporous carbon materials can enhance their capacitive performance,conflicting reports and the lack of a definitive correlation between capacitance and pore size remain issues[1].Understanding the relationship between the structure of carbon materials and their capacitance is crucial for designing devices with high energy densities.
基金supported by the National Natural Science Foundation of China(Grant Nos.12135019 and 52202154)the 2115 Talent Development Program of China Agricultural University,the Scientific Research Start-up Fund for Outstanding Talent of China Agricultural University,Chinese Universities Scientific Fund,and High-performance Computing Platform of China Agricultural University。
文摘Piezoelectric ceramics provide high strain and large driving forces in actuators.A large electrostrain can be realized by the introduction of point defects such as vacancies,interstitial defects,and substitution defects.With Mn doping,a significant increase in the reversible electrostrain from 0.05%to 0.17%could be achieved in potassium niobite lead-free piezoelectric ceramics.The origins of the large electrostrain were analyzed via in situ X-ray diffraction(XRD)under an electric field.The electrostrain and other typical electrical properties of the samples were measured at various temperatures,which enabled the ceramics to perform under a very wide temperature range,such as−80–130℃ for the 0.5 mol%Mn-doped sample with low dielectric loss(≤0.02).More importantly,combined with characterizations of the defect behavior by thermally stimulated depolarization current(TSDC),the failure mechanisms of electrostrain in a hightemperature environment could be revealed,which was associated with synergistic damage to the defects caused by the electric field and high temperature.The results can provide good ideas and a basis for the design of piezoelectric materials with good electrostrain stability over a wide temperature range.
