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Hexagonal manganites can exhibit the low-symmetry ferroelectric (FE) P63cm and partially undistorted anti-ferroelectric (PUA) P-3c1 states. The two states are accompanied by distinct sixfold vortex domain structures. The transition from the FE P63cm and PUA P-3c1 states (FE-PUA transition) is an effective means to control domain structures with distinct FE properties, which is of rich physical properties and potential applications. The FE-PUA transition can only be achieved by doping Ga on the Mn site of InMnO3, but the actual transition path and the associated domain structure evolution are still unclear. Namely, whether this transition goes through an intermediate P3c1 state remains an issue. In this work, we start from the Landau phenomenological theory to investigate the FE-PUA transition by directly tracking the domain structure evolution. The emerging 12-fold vortex domain structure at the intermediate stage of this transition indicates that this transition is not direct, and its actual path follows the P63cm → P3c1 → P-3c1 sequence, demonstrating the essential role of the intermediate P3c1 state. Besides, a pinning effect as a by-product is also discussed. This work comprehensively illustrates the characteristics of domain structure evolution during the FE-PUA transition, refining our understanding of the whole phase transition and topological physics associated with vortex domain structures in hexagonal manganites. [ABSTRACT FROM AUTHOR]

This paper studies the properties of the Fourier transform of the fuzzy function, and extends the classical Poisson integral formula on the half plane to the fuzzy case, obtaining the composition of the fuzzy set generated by a point in the complex field under the action of the fuzzy function. Further, we define and study the fuzzy Hilbert transform of fuzzy functions and their properties. We prove that when the fuzzy function degenerates to the classical case, the fuzzy Hilbert transform will degenerate to the classical Hilbert transform, which proves that the fuzzy Hilbert transform is an extension of classical transformations in the fuzzy function space. In addition, we point out and prove some properties of the fuzzy Hilbert transform. For some fuzzy functions that meet certain requirements, their fuzzy Hilbert transform is a fuzzy point on 0. [ABSTRACT FROM AUTHOR]

The Anwangshan gold deposit is located in the northwestern part of the Fengtai Basin, Western Qinling Orogen (WQO). The gold ore is hosted within quartz syenite and its contact zone. The U–Pb weighted mean age of the quartz syenite is 231 ± 1.8 Ma. It is characterized by high potassium (K2O = 10.13%, K2O/Na2O > 1) and high magnesium (Mg# = 55.31 to 72.78) content, enriched in large ion lithophile elements (Th, U, and Ba) and light rare earth elements (LREE), with a typical "TNT" (Ti, Nb, and Ta) deficiency. The geochemical features and Hf isotope compositions (εHf(t) = −6.68 to +2.25) suggest that the quartz syenite would form from partial melting of an enriched lithospheric mantle under an extensional setting. Three generations of gold mineralization have been identified, including the quartz–sericite–pyrite (Py1) stage I, the quartz–pyrite (Py2)–polymetallic sulfide–early calcite stage II, and the epidote–late calcite stage III. In situ sulfur isotope analysis of pyrite shows that Py1 (δ34S = −1.1 to +3.8‰) possesses mantle sulfur characteristics. However, Py2 has totally different δ34S (+5.1 to +6.7‰), which lies between the typical orogenic gold deposits in the WQO (δ34S = +8 to +12‰) and mantle sulfur. This suggests a mixed source of metamorphosed sediments and magmatic sulfur during stage II gold mineralization. The fluid inclusions in auriferous quartz have three different types, including the liquid-rich phase type, pure (gas or liquid)-phase type, and daughter-minerals-bearing phase type. Multiple-stage fluid inclusions indicate that the ore fluids are medium-temperature (concentrated at 220 to 270 °C), medium-salinity (7.85 to 13.80% NaCleq) CO2–H2O–NaCl systems. The salinity is quite different from typical orogenic gold deposits in WQO and worldwide, and this is more likely to be a mixture of magmatic and metamorphic fluids as well. In summary, the quartz syenite should have not only a spatio-temporal but also a genetical relationship with the Anwangshan gold deposit. It could provide most of the gold and ore fluids at the first stage, with metamorphic fluids and/or gold joining in during the later stages. [ABSTRACT FROM AUTHOR]

It is known that the utilization of exchange bias (EB) effect for data storage underscores its importance. However, achieving a giant EB effect with a small cooling field (HCF) in single-phase materials remains a challenge. This study unveils a giant EB value within a single-phase material, Fe2−xGaxTeO6 (FGTO), originating from the anchoring of spin-glass phase by antiferromagnetic order. Manipulating the relative strengths of the spin-glass and antiferromagnetic order parameters by Ga3+-substitution of Fe3+ ions in the Fe2TeO6 lattice governs the magnitude of the EB effect. It is found that FGTO single crystals synthesized via the chemical vapor transport do exhibit a remarkably large EB value as large as 1.5 T at x = 0.50 and a quite small cooling field HCF = 50 Oe. Investigations on the training effect, minor loop, and relaxation behavior unravel the intricate dynamics inherent to the spin-glass state. This study not only establishes a platform for exploring the EB effect in single-phase materials but also illuminates potential applications of FGTO in the realm of spintronics. [ABSTRACT FROM AUTHOR]

Hf0.5Zr0.5O2 (HZO) thin films are promising for applications in ferroelectric memories. However, these materials often face challenges, such as polarization fluctuations (e.g., fatigue and wake-up) and electric break-down incidents during the "1/0" write/read cycles, hindering their industrial application. Herein, fatigue, wake-up, and electric break-down seriously depend on both the electric field for polarization switching (Es) and the charge accumulation in the HZO film. More and more charges pin ferroelectric domains, and the sub-switching polarization introduces serious ferroelectric fatigue during the 1010 write/read cycles at Es ∼ 1.2Ec, where Ec is a ferroelectric coercive field. On the contrary, new charges increase rather slowly, and complete polarization switching is realized during the 1010 cycles at Es ∼ 1.5Ec, so the HZO film presents excellent polarization stability. A high Es ∼ 2Ec introduces the strong wake-up effect first; however, the serious charge accumulation largely increases leakage current and quickly introduces an electric break-down of the HZO film. Furthermore, it was found that the leakage current and dielectric permittivity can effectively monitor the charge accumulation and provide an early warning for fatigue and electric break-down. [ABSTRACT FROM AUTHOR]

Entropy engineering has emerged as an effective strategy to optimize the lattice and electronic structures of thermoelectric (TE) materials, with significant efforts toward achieving exceptional TE performance. In this study, we carried out entropy engineering on the well-known binary compound MnTe by both the partial Ge substitution of Mn and the mixture of AgBiTe2 in the form of a solid solution. Such an engineering strategy results in the formation of the high-entropy quintuple semiconductor MnGeAgBiTe4, stabilizes the single-phase rock-salt structure without the occurrence of impurity, and remarkably improves the TE properties. High-entropy engineering simultaneously enhances the carrier concentration and mobility in MnGeAgBiTe4 compared with pristine MnTe. Furthermore, the first-principles calculations reveal the multi-peak nature of MnGeAgBiTe4, in consistence with a high band effective mass of 5.1me estimated from the Pisarenko line. Consequently, an excellent power factor of 10.5 μW cm−1 K−2 and an ultralow lattice thermal conductivity κl ∼ 0.34 W m−1 K−1 at temperature T = 773 K are obtained in MnGeAgBiTe4. These superior electrical and thermal transport properties lead to a maximal ZT of ∼1.09 at T = 773 K and an average ZT of ∼0.90 from 400 K to 773 K. [ABSTRACT FROM AUTHOR]

The MAPbBr3 halide perovskite with a cubic paraelectric phase exhibits excellent semiconductor properties. Here, an interfacial polarization (Pin) at the ITO/MAPbBr3 Schottky junction can largely enhance photovoltaic current and be applied in the light and force multifunctional detector. An external force can alter the Pin and increase the photocurrent of the ITO/MAPbBr3/spiro‐OMeTAD/ITO detector, and a 1 N force increases the short‐circuit photocurrent by 120%. Furthermore, the ITO/MAPbBr3/ITO structure with one ITO surface in light and another ITO surface in dark exhibits an equivalent piezoelectric coefficient (d33) of up to 83 pC N−1 since the Pin and the corresponding photovoltaic current dynamically change with periodic external force. The light and force multifunctional detectors will promote the development and blend of optoelectronic devices and MEMS. [ABSTRACT FROM AUTHOR]