Manipulating the magnetism and resistance state of Mn:ZnO/Pb(Zr0.52Ti0.48)O3 heterostructured films through electric fields
23 May 2018-Applied Physics Letters (AIP Publishing LLC AIP Publishing)-Vol. 112, Iss: 21, pp 212902
TL;DR: In this article, an effective method for modulating the magnetism of magnetic semiconductors and providing a promising avenue for multifunctional devices with both electric and magnetic functionalities is presented.
Abstract: Mn:ZnO/Pb(Zr0.52Ti0.48)O3 (PZT) heterostructured films have been prepared on Pt/Ti/SiO2/Si wafers by a sol-gel process. Nonvolatile and reversible manipulation of the magnetism and resistance by electric fields has been realized. Compared with the saturation magnetic moment (Ms) in the +3.0 V case, the modulation gain of Ms can reach 270% in the −3.0 V case at room temperature. The resistance change is attributed to the interfacial potential barrier height variation and the formation of an accumulation (or depletion) layer at the Mn:ZnO/PZT interface, which can be regulated by the ferroelectric polarization direction. The magnetism of Mn:ZnO originates from bound magnetic polarons. The mobile carrier variation in Mn:ZnO, owing to interfacial polarization coupling and the ferroelectric field effect, enables the electric manipulation of the magnetism in the Mn:ZnO/PZT heterostructured films. This work presents an effective method for modulating the magnetism of magnetic semiconductors and provides a promising avenue for multifunctional devices with both electric and magnetic functionalities.
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TL;DR: The mechanism of RS behavior in ferroelectric heterostructures is briefly introduced, the methods used to improve RS performance in recent years are summarized, existing problems in this field are identified, and future development trends are highlighted.
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TL;DR: In this article, both resistive and magnetization switching were realized in Pt/NiFe1.95Cr0.05O4 (Cr-NFO)/Pt devices by the manipulation applied electric field process, where a CrNFO switching layer was prepared by a facile chemical solution process method.
Abstract: In this letter, both resistive and magnetization switching were realized in Pt/NiFe1.95Cr0.05O4 (Cr-NFO)/Pt devices by the manipulation applied electric field process, where a Cr-NFO switching layer was prepared by a facile chemical solution process method. The Cr-NFO based devices exhibited stable unipolar switching behavior, uniform operating voltages, good endurance (>103 cycles), large ON/OFF memory window (>102), and excellent retention characteristic time (>105 s at 25 °C). Meanwhile, the saturation magnetization of Cr-NFO based devices showed reversible switching in different resistance states. The significant change between the high magnetization state and the low magnetization state could reach as high as ∼50% during resistive switching operation. The ON-OFF switching can be achieved at room temperature in resistive and magnetization switching. The proposed physical mechanism of resistive and magnetized switching of Cr-NFO based devices was related to the formation and rupture of conduction filaments consisting of oxygen vacancies and cations, which was based on the conversion of Fe (Fe3+ → Fe2+) and Cr (Cr3+ → Cr4+) valence change, redox reaction, and Joule heating effects. The coexistence of resistive and magnetization switching in ferrite thin film based devices has potential application in nonvolatile memory and magneto-electric coupling devices.
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TL;DR: In this paper, the anomalous photovoltaic effect and resistive switching behaviors in ferroelectric materials attract much attention in recent years, and the conductive mechanisms and research progresses of the two effects were discussed in this study.
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TL;DR: In this article , the authors present a review of three physical mechanisms which lead to resistive switching: electrochemical metallization, valence change mechanism, and ferroelectric polarization.
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7 citations
TL;DR: For the first time, a weak ferromagnetic hysteresis loop at room temperature has been observed in PbZr1−xTixO3 (PZT) single crystals.
Abstract: For the first time, a weak ferromagnetic hysteresis loop at room temperature has been observed in PbZr1−xTixO3 (PZT) single crystals. The occurrence of these properties has been related to the presence of oxygen vacancies and/or lower oxidation state of titanium. This proves that ferroelectric and ferromagnetic properties can occur simultaneously in this “famous” piezoelectric perovskite without any magnetic dopant.
5 citations
References
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TL;DR: It is proposed thatferromagnetic exchange here, and in dilute ferromagnetic nitrides, is mediated by shallow donor electrons that form bound magnetic polarons, which overlap to create a spin-split impurity band.
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2,743 citations