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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 study presents the modelling of magnetocaloric effect of Pr0.67Sr0.33MnO3 nanoparticles by using the mean-field theory (MFT). Theoretical calculations were used around the Curie temperature (TC) to simulate the temperature dependence of magnetic entropy change under several applied magnetic fields. The obtained results were compared with experimental data computed using the Maxwell relation. Discrepancy between the two methods confirm the invalidity of MFT for modelling the magnetocaloric properties of Pr0.67Sr0.33MnO3 nanoparticles. This invalidity suggests the presence of critical fluctuations near the TC, which can be attributed to the presence of disordered surface and/or magnetic frustration, and highlights the limitation of the used model. [ABSTRACT FROM AUTHOR]

Complex oxide heterointerfaces and heterostructures have demonstrated enormous emergent phenomena over the last decades, attributed to the reconstructions of mis‐matched crystalline structure, polarity, and spin ordering across the heterointerfaces. This work employs the heterostructures of La0.7Sr0.3MnO3 and CaFeO2.5 as model system to demonstrate an interface‐specific oxygen migration/reconstruction across the interfaces due to the mismatched chemical potential, which dramatically influences the ferromagnetic and electronic states of La0.7Sr0.3MnO3 layer. Specifically, the alternative stacking of octahedral (Oh) and tetrahedral (Td) layers in CaFeO2.5 are used to form two distinct heterointerfaces, namely the Oh‐Td and the Oh‐Oh interfaces with the adjacent La0.7Sr0.3MnO3 layer. Interestingly, the oxygen ion migrates toward opposite directions across the interface for these two cases, in which the CaFeO2.5 layer acts as an “oxygen pump” and manipulates the oxygen contents of its adjacent La0.7Sr0.3MnO3 layers. Such manipulation leads to a dramatically changed ferromagnetic transition temperature for the heterostructure with the Oh‐Td and Oh‐Oh interface. This work establishes a feasible and efficient strategy to control the oxygen ionic distribution through atomic‐scale interface design and opens up new opportunities to exploit emergent states at the complex oxide heterostructures through selective oxygen ion evolution. [ABSTRACT FROM AUTHOR]

This work investigates the potential of ZrO 2 /MoO 3 nanocomposites as catalysts for hydrogen production through NaBH 4 methanolysis. The samples were prepared by controlled thermal calcination and characterized using various techniques like XRD, FTIR, Raman, SEM, and surface area BET analysis. Rietveld refinements verified the presence of the ZrO 2 monoclinic phase with the space group P 2 1 / c in all samples and a second orthorhombic MoO 3 phase with the space group Pnma. The average crystal size decreased from 44 to 40 nm. FTIR and Raman spectroscopy confirmed the successful preparation of ZrO 2 /MoO 3 nanocomposites. SEM analysis showed ZrO 2 particles and MoO 3 nanoparticles adhered to the ZrO 2 surface, potentially creating a rougher texture. The results confirmed the formation of ZrO 2 /MoO 3 nanocomposites with increasing MoO 3 content, leading to an increased surface area of 19–23 m2/g. The catalytic performance evaluation revealed that the sample containing 30 % MoO 3 (ZM3) exhibited the highest hydrogen generation rate of 18,451 mL/g. min at 30 °C. The calculated activation energy for ZM3 was 18.78 kJ/mol, suggesting efficient hydrogen generation at moderate temperatures. [ABSTRACT FROM AUTHOR]

This study analyzes how adding europium and transition metals (Cu, Ag, and Au) at a 12.5% concentration to magnesium oxide (MgO) affects its physical characteristics and potential uses. To do so, the full potential linearized augmented plane wave (FP-LAPW) method, based on spin-polarized density functional theory (SP-DFT), is used to derive the results. Wu and Cohen's generalized gradient approximation (GGA-WC) described the exchange-correlation potential. The modified Becke-Johnson exchange potential (TB-mBJ) was also used to improve the findings of optoelectronic properties. When Eu and TM (Cu, Ag, and Au) impurities are co-doped into the nonmagnetic (NM) semiconductor MgO, the structural optimization results show that the lattice constants increase, and the bulk modulus decreases with increasing the atomic number of transition metals. The resulting dilute magnetic oxides (DMOs) are stable in the spin-polarized ferromagnetic (FM) phase, and the formation energy values confirm their stability in the F m 3 ̄ m cubic structure, with the lowest value belonging to Eu 0. 1 2 5 TM 0. 1 2 5 Mg 0. 7 5 0 O. Similarly, calculations of electronic properties using the WC-mBJ functional demonstrate that all compounds have an indirect half-metallic bandgap at L- Γ equal to 2.53, 2.49, and 1.39 eV for Eu 0. 1 2 5 Cu 0. 1 2 5 Mg 0. 7 5 0 O, Eu 0. 1 2 5 Ag 0. 1 2 5 Mg 0. 7 5 0 O, and Eu 0. 1 2 5 Au 0. 1 2 5 Mg 0. 7 5 0 O, respectively. They have an integer magnetic moment of 6 μ B . The density of states shows that at the Fermi level, the 4f-Eu, d-TM, and p-O states give rise to new energy levels. This indicates that the f–p–d hybridization provides this system with its FM properties. Also, these compounds' dielectric function and absorption spectra are calculated and analyzed to learn more about their optical properties. The results provide insight into the optical behavior of the materials. It is observed that the co-doped compounds exhibit greater optical absorbance than their un-doped MgO counterparts do. This theoretical investigation opens the way to preparing high magnetic moment DMOs using TM and rare earth as dopants suitable for spintronic and UV devices. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry." It includes information about the articles and papers featured in the journal's latest issue. The topics covered range from the synthesis of catalysts to the study of coordination polymers and the design of anticancer therapy. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The given document is a list of papers published in the journal Dalton Transactions. The papers cover a range of topics including the synthesis and properties of various compounds, the development of new materials for applications such as light-emitting diodes and supercapacitors, and investigations into the behavior of different chemical compounds. The document provides a comprehensive overview of the research being conducted in the field of chemistry. [Extracted from the article]

Although extensive work has already been done on bulk La1−xSr1+xCoO4 layered oxides, there is very limited studies on their nano-crystalline nature, particularly for those with a higher Sr level (x ≥ 0.4), which may exhibit interesting magnetic properties and in particular photocatalytic properties because of their enhanced surface area. Moreover, the phases with higher Sr doping levels can be formed only at higher temperatures, which otherwise contain significant amounts of impurities. In order to synthesize them in a nanocrystalline form in the pure state at the lowest possible temperature, we applied a glycine nitrate combustion method using excess fuels for the synthesis of nanocrystalline La1−xSr1+xCoO4 (x = 0.0, 0.2, 0.4 and 0.6) layered perovskite oxides. Efforts were also made to synthesize phases with x > 0.6 but remained unsuccessful. The prepared nanophases were thoroughly characterized using PXRD, XPS, SEM, SQUID VSM and UV-DRS to examine the structural, morphological, optical, magnetic and photocatalytic properties. All the phases exhibit mixed valence states of +3 and +4 of Co, as confirmed by XPS analysis, which has a remarkable effect on various physical properties, especially magnetic and photocatalytic properties. An abrupt transition in magnetic behaviour from antiferromagnetic for x = 0 and 0.2 phases to ferromagnetic in case of x = 0.4 and 0.6 was observed. The optical band gap values (Eg) of all the synthesized nanophases obtained from DRS are in the visible range (1.57 to 1.47 eV), which make them suitable and reliable photocatalysts for dye degradation. Moreover, the synthesized nanophases were assessed for their photocatalytic activity by employing rhodamine B (RhB) dye as a model contaminant. The results revealed that the La0.4Sr1.6CoO4 photocatalyst efficiently and swiftly degraded RhB within 60 min. Considering the performance of the La0.4Sr1.6CoO4 photocatalyst, the study was expanded to include the degradation of other organic dye pollutants, namely, methyl orange (MO), methylene blue (MB) and a ternary combination of these contaminants (RhB + MB + MO). [ABSTRACT FROM AUTHOR]

Wastewater contamination, particularly from dye effluents containing organic colorants originating from industrial sources, represents a significant environmental and public health hazard. This study is dedicated to removal of these abundant coloured effluents in wastewater, addressing the imperative need for effective remediation strategies to safeguard ecosystems and human well‐being. In this regard, bare and K‐doped perovskite manganites La0.5Nd0.2Ca0.3MnO3 (LCM) and La0.5Nd0.2Ca0.25K0.05MnO3 (LCKM) nanoparticles respectively were synthesized in order to study their catalytic behaviour for degradation of coloured effluents. The Rietveld analysis applied to the X‐ray diffraction data provides confirmation of orthorhombic symmetry. For exploring the catalytic properties, rhodamine‐B (RhB) dye was chosen as model dye pollutant. The achieved degradation efficiency is substantial, reaching 99 % within a brief period of 10–12 min. Following these results, we have also carried out the degradation of some other dyes such as methylene blue (MB) and methyl orange (MO). It was observed that MO dye was more efficiently degraded in quick time as compared to all the other dyes due to its anionic nature. Furthermore, the comparative catalytic efficiencies of LCM and LCKM catalysts were explained on the basis of Mn3+/Mn4+ redox pairs and it was observed that LCKM had shown better degradation efficiency than LCM. [ABSTRACT FROM AUTHOR]

The development of effective photocatalysts is critical for the photo/redox reaction of noxious Hg(II) ions and Hgo in environmental engineering and purification. In this contribution, Li 2 MnO 3 nanoparticles (NPs) were anchored mesoporous CeO 2 networks to design photocatalysts with high harvest of visible light, and the obtained Li 2 MnO 3 /CeO 2 nanocomposites were utilized for photoreduction of Hg(II) ions under visible illumination. The TEM and XRD results showed the formation of Li 2 MnO 3 and CeO 2 with the monoclinic and cubic fluorite structures, and the particle size is about 10–20 nm. The enhancement of light absorption of Li 2 MnO 3 /CeO 2 nanocomposites could create considerable photoinduced carriers during the photocatalytic reactions. The incorporation of Li 2 MnO 3 and CeO 2 NPs demonstrated outstanding photocatalytic performance compared with pristine CeO 2 NPs, and the optimum 9%Li 2 MnO 3 /CeO 2 nanocomposite achieved 98 % of the reduction Hg(II) ability within 60 min. The rate constant for 9 % Li 2 MnO 3 /CeO 2 photocatalyst is ∼ 6.47 and 3.85 times greater than Li 2 MnO 3 and CeO 2 NPs. The superior photocatalytic performance of Li 2 MnO 3 /CeO 2 nanocomposites was ascribed to the efficient separation of photocarriers due to the formation of S-scheme heterojunction, the large surface area, and mesoporous structures. The obtained Li 2 MnO 3 /CeO 2 nanocomposite was highly stable and efficient for the Hg(II) photoreduction runs up to five successive experiments under similar conditions. Moreover, the possible mechanism over heterojunctions Li 2 MnO 3 /CeO 2 nanocomposites toward the reduction of Hg(II) ions is examined as well. The formation of S-scheme heterojunction photocatalyst provides better photocatalytic applications in terms of air purification, hydrogen production, and water treatment. [ABSTRACT FROM AUTHOR]

Complex oxide heterointerfaces provide a spacious arena for creating emergent phenomena that are unattainable in the constituent bulk counterparts. Herein, The BaTiO3/La1‐xSrxMnO3 [BTO/LSMO (x)] superlattice (SL) as a model system to investigate the intimately coupled interfacial effects and their resultant phenomena is focused on. The experimental and Density Functional Theory (DFT) calculations reveal that the induced magnetism on Ti originates from both the charge transfer process between Mn and Ti at the titanate/manganite heterointerfaces and the cation intermixing, both contributing comparably to the overall magnetic effect. Upon changing x, the orbital reconstruction of the Mn 3d electrons, tailored by the strain state of the LSMO (x) layers, efficiently modifies the magnetic exchange coupling between Mn–Ti and Mn–Mn at the interfaces, which are proved to account for the modulations of the macroscopic magnetism of the SLs. This work demonstrates the significance of interfacial reconstructions for magnetism, paving a new pathway to manipulate the magnetic properties of artificial oxide heterostructures. [ABSTRACT FROM AUTHOR]

The ability to accommodate multiple principal cations within a single crystallographic structure makes high entropy oxides (HEOs) ideal systems for exploring new composition–property relationships. In this work, the high-entropy design strategy is extended to strained single-crystal HEO-manganite (HEO-Mn) thin films. Phase-pure orthorhombic films of (Gd0.2La0.2Nd0.2Sm0.2Sr0.2)MnO3 were deposited on three different single-crystal substrates: SrTiO3 (STO) (100), NdGaO3 (110), and LaAlO3 (LAO) (100), each inducing different degrees of epitaxial strain. Fully coherent growth of the thin films is observed in all cases, despite the high degree of lattice mismatch between HEO-Mn and LAO. Magnetometry measurements reveal distinct differences in the magnetic properties between epitaxially strained HEO-Mn thin films and their bulk crystalline HEO counterparts. In particular, the bulk polycrystalline HEO-Mn shows two magnetic transitions as opposed to a single one observed in epitaxial thin films. Moreover, the HEO-Mn film deposited on LAO exhibits a significant reduction in the Curie temperature, which is attributed to the strong variation of the in-plane lattice parameter along the thickness of the film and the resulting changes in the Mn–O–Mn bond geometry. Thus, this preliminary study demonstrates the potential of combining high entropy design with strain engineering to tailor the structure and functionality of perovskite manganites. [ABSTRACT FROM AUTHOR]

The Sm0.47La0.20K0.33MnO3 perovskite manganite was synthesized using the solid-state reaction method and its structural, magnetic, and critical properties were investigated. This work analyzed the structural characteristics of our sample through Rietveld refinement of the X-ray diffraction pattern and Hirshfeld surface mapping (HS) techniques. It was shown that the sample crystallized in the space group Pnma, with the lattice parameters: a = 5.461 (4) Å, b = 5.478(1) Å, and c = 7.706(8) Å. The Mn–O bond length ~ 1.9 Å obtained from the Rietveld refinement, agrees with the minimum distances between Mn and O atoms obtained from the characteristic 2D fingerprint plots of this manganite. From M vs. T measurements in the range of 5 K < T < 300 K and isothermal measurements M (H) in the range of 0 T < H < 6.5 T , two phase transitions were observed: (i) a paramagnetic (PM)—ferromagnetic (FM) second-order phase transition, and (ii) a FM—spin-glass-like transition. The latter is associated with the presence of samarium in the crystalline structure of the manganite studied. Furthermore, a collective freezing state occurs at T B = 72.83 K . The behavior of the inverse of susceptibility χ - 1 (T) vs. T shows the coexistence of FM clusters within the PM state ( T > 184 K ). Modified Arrott plots (applied to 3D-Heisenberg, 3D-Ising, and Tricritical mean-field models), as well as the Kouvel-Fisher method, were employed to obtain the critical coefficients that were found to be β = 0.367 , γ = 1.330 , and δ = 4.776 for the Sm0.47La0.20K0.33MnO3 manganite. It was confirmed that both critical exponents (β and γ) satisfy the Widom scaling relation (δ = 1 + γ β) . However, a slight deviation from the theoretical values exists of the critical exponent δ obtained with the 3D Heisenberg model. This may be due to the nanoscale dimensions of the secondary phase KMn 2 O 6 particles. In conclusion, critical coefficients and observed phase transitions are significant because they provide guidance for theoretical modeling, enabling real-world applications in diverse technical domains, and shed light on material behavior, all of which contribute to our understanding of manganites. Based on the results of the search, it appears that a better understanding of the critical magnetic behavior in polycrystalline manganites may greatly improve future research and applications in the following areas: Hard disk drives HDDs and magnetic tapes are magnetic data storage devices which can benefit from manganite research to be advanced. Spintronics is a technology, which is based on electron spin polarization mechanism to process information. It utilizes manganites as an important material. [ABSTRACT FROM AUTHOR]

Conducting optimization calculations for thermoelectric performance can be beneficial in guiding the direction of further experimental work. In our study, we utilize a combination of the first principle, Boltzmann transport and restructured single parabolic band model to investigate the half-doped semiconductors based on manganite. Ca0.5La0.5− x Bi x MnO3 (x = 0, 0.25) as samples shows the power factor (PF) optimum value of 30% and 69% for x = 0 and 0.25, respectively at a temperature of 800 K. In addition, both samples show two to three orders of magnitude smaller lattice thermal conductivity than their electronic thermal conductivity. This excludes complex phononic transport mechanisms from the calculation of the figure of merit (ZT). The ZT calculations of Ca0.5L0.5MnO3 and Ca0.5L0.5− x Bi x MnO3 are corrected by the ratio of the transport relaxation time of electrical conductivity to the transport relaxation time of electronic thermal conductivity by the Lorenz number, resulting in ZT values of 0.063 and 0.327 at a temperature of 800 K, respectively. [ABSTRACT FROM AUTHOR]

Synthesize of La0.75Ba0.05Ca0.2Mn0.93Cr0.07O3 nanoparticle manganite were carried by Sol gel method. Based on the Rietveld method, the refinement results identify the crystallization of our samples orthorhombic structure with the Imma symmetry. The temperature dependence of magnetization M(T) curves at 0.05 T applied magnetic field indicate that the samples undergo a ferromagnetic paramagnetic transition around the Curie temperature TC = 265 K. The determined Curie temperature values was deduced from the minima of dM/dT data. The magnetocaloric results, show that the highest magnetic entropy change values was found to be 3.6 J−1 kg−1 K−1 in our sample. This considerable magnetocaloric value exhibiting our samples makes it promising for spintronic devices. Using, the modified Arrott plot, Kouvel Fisher technique, and the critical isotherm, the universal data were analyzed and found to obey the mean field model for La0.75Ba0.05Ca0.2Mn0.93Cr0.07O3. [ABSTRACT FROM AUTHOR]

Although the dynamics of domain growth has been a long-standing topic in ferroic systems, its science complexity and important guidance to practical applications cannot be overemphasized. Highly anisotropic systems with only domain-wall-type defects and roughly isotropic systems with only vortex-type defects have been extensively studied as two ideal and extreme examples in terms of domain growth dynamics. The domain growth processes in these two types of systems are believed to follow two different scaling laws. The driving forces behind are domain wall motion and vortex–antivortex annihilation, respectively. However, no realistic ferroic systems have ever been found to exhibit a domain growth process that strictly follows these scaling laws. Fortunately, we now have a realistic ferroic system, i.e., the ferroelectric hexagonal manganite family in which the aforementioned two types of defects coexist. This system supports a fascinating topological vortex–antivortex domain structure and is a unique platform for probing a generalized theory on the domain growth dynamics that covers the two extremes. In this work, we investigate this vortex–antivortex domain structure and its growth dynamics within the framework of the Landau theory using phase-field simulations. It is revealed that morphology of this domain structure can be controlled by a correlation length Lc that is different from the conventional correlation length. More importantly, this domain structure can be seen as an intermediate state between the two extremes in terms of domain growth dynamics. When Lc is very small, the domain growth process in this domain structure is driven by domain wall motion and follows the well-known Allen–Cahn scaling law. As Lc increases, vortex–antivortex annihilation will dominate the domain growth process and the scaling law will need a logarithmical correction. The present work provides a comprehensive understanding of the domain growth behavior in such a realistic ferroic system of much attention and represents a substantial extension of domain growth dynamics toward complicated multi-defect systems. [ABSTRACT FROM AUTHOR]

This work aims to investigate the structural stability, magnetic and electronic properties of M3AlC antiperovskites using density functional theory (DFT) and Monte Carlo simulation. The obtained ground state results reveal that the antiperovskites M3AlC are stable in the ferromagnetic (FM) state with a metallic character. The calculated total magnetic moments are 5.21 μ B and 3.34 μ B for Mn3AlC and Fe3AlC, respectively, with the total moments mainly from the M atom. The ferromagnetic behavior is confirmed by computing the density of state at Fermi level and verified the Stoner criterion. The magnetic and magnetocaloric behavior of M3AlC is investigated using Monte Carlo simulation and the obtained results demonstrate that the transition from ferromagnetic to paramagnetic state occurs at T C = 3 0 0 K and T C = 2 3 0 K for Mn3AlC and Fe3AlC, respectively. These values of T C are in good agreement with the experimental results. The magnetocaloric effect and critical behavior are studied and the obtained values of magnetic entropy change | Δ S mag | at 4.5 T is about 4.242 J/kg.K and 3.666 J/kg.K and the relative cooling power (RCP) are 342.434 J/kg.K and 325.26 J/kg.K for Mn3AlC and Fe3AlC at 4.5T, indicating that these compounds are more appropriate for magnetic refrigeration. Finally, the critical exponents (β , γ , δ) are calculated and the obtained values are close to the values of mean-field model. [ABSTRACT FROM AUTHOR]

We herein provided a systematical determination of the structural and magnetic properties, especially of the magnetocaloric effect (MCE) and magnetocaloric performances of four rare-earth oxychlorides, i. e., the RE OCl (RE = Ho, Dy, Tb and Gd) compounds. The studied RE OCl compounds are all crystallized in the tetragonal matlockite structure (P 4/ nmm space group) and the RE , O, and Cl elements are with the RE 3+, O2−, and Cl− valence states, respectively. The DyOCl, TbOCl and GdOCl compounds reveal an antiferromagnetic transition at around approximate 9.5, 3.7 and 4.8 K, respectively. The magnetocaloric performances are checked by the maximum magnetic entropy change, relative cooling power, and temperature-averaged entropy change with 5 K lift, which are found to be 14.16 J/kgK, 375.55 J/kg and 13.89 J/kgK for HoOCl, to be 14.88 J/kgK, 488.14 J/kg, and 14.60 J/kgK for DyOCl, to be 14.59 J/kgK, 419.67 J/kg, and 14.42 J/kgK for TbOCl, and to be 16.16 J/kgK, 213.68 J/kg, and 14.39 J/kgK for GdOCl, with the magnetic field change of 0–7 T, respectively. [ABSTRACT FROM AUTHOR]

The Ca0.6−xSr0.4HoxMnO3−δ (x = 0.05, 0.10, and 0.15) manganites with an orthorhombic crystal structure (space group Pbnm) have been produced via citrate–nitrate route in air. The electron donor holmium (Ho3+) and oxygen nonstoichiometry strongly affect the electrical conductivity (σ), Seebeck coefficient (S), thermal conductivity (κ), and thermal expansion. The increase in the absolute values of S with temperature and the decline of σ above 500 K are explained by the decrease in the concentration of Mn3+ ions due to their disproportionation into Mn2+ and Mn4+ ions. The equilibrium constant of disproportionation, the concentration and mobility of charge carriers depend on temperature and can be derived from the data for S(T) and σ(T). The formation of Mn3+ ions as a result of partial removal of oxygen from the manganites has a strong influence on their properties above 1000 K. Temperature-activated character of mobility and the values of S are consistent with the adiabatic small polaron transport mechanism in Ca0.6−xSr0.4HoxMnO3−δ. [ABSTRACT FROM AUTHOR]

We report the studies of structure and properties of a quasi-one-dimensional (quasi-1D) compound ${\rm BaTiS}_{3}$ BaTiS 3 under pressure. The poly-crystalline samples are synthesized by solid-state reaction method and single-crystalline samples are produced by chemical vapor transport method. The XRD measurement under ambient pressure confirms the hexagonal structure, which consists of face-sharing octahedral ${\rm TiS}_{6}$ TiS 6 chains along c-axis and displays a quasi-1D feature. When applying pressure, the synchrotron X-ray diffraction experiments show that the sample undergoes a phase transition from hexagonal phase to orthorhombic phase at around 10 GPa due to the zig–zag deformation of ${\rm TiS}_{6}$ TiS 6 chains, while the quasi-1D structure is reserved. At ambient pressure, ${\rm BaTiS}_{3}$ BaTiS 3 exhibits an insulating behavior with a band gap about 0.273 eV. When applying pressure, the sample undergoes a crossover from insulator to metal due to the enhancement of inter-chain electron hopping. [ABSTRACT FROM AUTHOR]

The Ca0.6−xSr0.4HoxMnO3−δ (x = 0.05, 0.10, and 0.15) manganites with an orthorhombic crystal structure (space group Pbnm) have been produced via citrate–nitrate route in air. The electron donor holmium (Ho3+) and oxygen nonstoichiometry strongly affect the electrical conductivity (σ), Seebeck coefficient (S), thermal conductivity (κ), and thermal expansion. The increase in the absolute values of S with temperature and the decline of σ above 500 K are explained by the decrease in the concentration of Mn3+ ions due to their disproportionation into Mn2+ and Mn4+ ions. The equilibrium constant of disproportionation, the concentration and mobility of charge carriers depend on temperature and can be derived from the data for S(T) and σ(T). The formation of Mn3+ ions as a result of partial removal of oxygen from the manganites has a strong influence on their properties above 1000 K. Temperature-activated character of mobility and the values of S are consistent with the adiabatic small polaron transport mechanism in Ca0.6−xSr0.4HoxMnO3−δ. [ABSTRACT FROM AUTHOR]

Ruddlesden–Popper manganites are strongly correlated, quasi two-dimensional systems with highly tunable functional properties, which can, for example, be controlled by composition, strain, and defects. Praseodymium calcium manganite is a particularly interesting Ruddlesden–Popper system due to its remarkably high temperature at which ordering phenomena set in, enabling correlation physics above room temperature. However, in order to utilize the correlation phenomena and the quasi-two-dimensionality of the Ruddlesden–Popper systems for applications, one needs to grow thin film junctions, making it necessary to control the structure–property relation of Ruddlesden–Popper thin films. Here, we present a cryogenic transmission electron microscopy study of praseodymium calcium manganite thin films, deposited on niobium doped strontium titanate substrates, where we analyze the structure of the manganite thin film, as well as the effect of the epitaxial strain and defects on the charge/orbital order of the system. We identify a structural phase transition above the onset of charge/orbital order, frequently occurring extended defects and the temperature dependence and spatial distribution of charge/orbital ordering in the film. Our results show in detail the relationships between strain/defects and properties of the ordered phases and thus give important insights into how to tailor the functional properties of thin film junctions of strongly correlated materials. [ABSTRACT FROM AUTHOR]

The generation of spin current in materials with high spin–orbit coupling is one of the primary topics for future spintronic applications. In this context, the high conversion efficiency of spin current to charge current is desired. Ferromagnetic resonance (FMR)-based inverse spin Hall effect (ISHE) is a quite popular method to study such spin-to-charge conversion. Here microwave frequency plays a crucial role in generating spin current which further gets converted to charge current due to spin–orbit interaction of the given material. In this work, we show the effect of microwave frequency on spin-to-charge current conversion efficiency in La 0. 6 7 Sr 0. 3 3 MnO3/Pt heterostructure prepared by oxygen-assisted molecular beam epitaxy (OMBE). From the ISHE analysis the maximum spin pumping voltage of ∼98 μV has been observed. Further spin Hall angle has been calculated for different frequencies and the maximum calculated value (∼0.06) for this system has been obtained at 14 GHz. [ABSTRACT FROM AUTHOR]

The evolution of multifunctional materials is an outstanding research area, which aims to improve the versatility of materials according to their broad domains of usage. Focus interest was paid here to the orthophosphate compound, in particular, the olivine NaMnPO4 material. This compound was synthesized by a solid‐state method and investigated using numerous techniques. Primary room‐temperature structural analysis evidences the sample synthesized in the orthorhombic structure and its phase purity. The sample's average grain size was calculated to be around 420 nm. Further, the band gap for our material was found to be (Eg=4.4 eV) by optical analysis of UV‐visible spectroscopy, revealing that our compound is a potential candidate for optoelectronic applications. The electrical behavior study's main results confirm the ferroelectric character of the sample and support the aim of deepening the knowledge of the material according to its thermally stimulated conduction processes through impedance spectroscopy. Electrical studies revealed the dominant transport processes across various temperature and frequency ranges, leading to the NSPT model. The frequency dependency relates to frequency‐dispersive dielectric spectra, conduction mechanisms, and relaxation phenomena. The obtained results show perspective and suggest that the material under study has a wide range of potential electronic applications. [ABSTRACT FROM AUTHOR]

The evolution of multifunctional materials is an outstanding research area, which aims to improve the versatility of materials according to their broad domains of usage. Focus interest was paid here to the orthophosphate compound, in particular, the olivine NaMnPO4 material. This compound was synthesized by a solid‐state method and investigated using numerous techniques. Primary room‐temperature structural analysis evidences the sample synthesized in the orthorhombic structure and its phase purity. The sample's average grain size was calculated to be around 420 nm. Further, the band gap for our material was found to be (Eg=4.4 eV) by optical analysis of UV‐visible spectroscopy, revealing that our compound is a potential candidate for optoelectronic applications. The electrical behavior study's main results confirm the ferroelectric character of the sample and support the aim of deepening the knowledge of the material according to its thermally stimulated conduction processes through impedance spectroscopy. Electrical studies revealed the dominant transport processes across various temperature and frequency ranges, leading to the NSPT model. The frequency dependency relates to frequency‐dispersive dielectric spectra, conduction mechanisms, and relaxation phenomena. The obtained results show perspective and suggest that the material under study has a wide range of potential electronic applications. [ABSTRACT FROM AUTHOR]

In this work, we report the effect of Zn concentration on structural, magnetic and magnetocaloric properties of (0.75)La 0.62 Nd 0.05 Ba 0·33 MnO 3 /(0.25)Ni 1- x Zn x Fe 2 O 4 (x = 0.5, 0.6 and 0.7) nanocomposites. The samples with different compositions were synthesized by co-precipitation process. The XRD analysis confirms the presence of both phases namely perovskite La 0.62 Nd 0.05 Ba 0·33 MnO 3 and spinel NiZnFe 2 O 4 and further proved by TEM analysis. Room Mössbauer measurements get insights information about the effect of Zn content in the hyperfine parameters and magnetic transition. Magnetic measurements M(T) reveal the presence of a magnetic transition from paramagnetic (PM) to ferromagnetic (FM) phase in the vicinity of Curie temperature. With decreasing Zn concentration, the Curie temperature increases as well as the maximum entropy change. [ABSTRACT FROM AUTHOR]

We prepared ultrafine MnCo 2 O 4 particles using a facile sol–gel autocombustion method. The structural and vibrational characterizations confirmed the formation of a pure cubic spinel phase in as-synthesized MnCo 2 O 4 particles. The surface morphology analyses revealed the porous structure with an average particle size of 5 nm and uniform distribution of manganese (Mn), cobalt (Co), and oxygen (O) in the particles. We observed the presence of multiple valence states of Mn and Co, occupying both tetrahedral and octahedral sites, enhancing our insight into the material's electronic properties and structural configuration. Our magnetization studies unveiled a Curie Temperature (T C) of 185 K with ferrimagnetic ordering below T C , resulting in substantial magnetization (9.8 emu/g) and coercivity (3.46 kOe) at 2 K and weak magnetic behavior above T C. This is attributed to the finite size and surface effects. Furthermore, the incorporation of MnCo 2 O 4 nanoparticles and graphene oxide into a polyurethane foam matrix resulted in an excellent sound absorption coefficient of 90 % at 2000 Hz. This outstanding acoustic performance underscores the versatile applications of MnCo 2 O 4 nanoparticles in diverse noise mitigation applications. [Display omitted] [ABSTRACT FROM AUTHOR]

We report on the effects of Ca doping on the structural and magnetic characteristics of ZnO oxide nanoparticles (NPs) (Zn0.96Ca0.04O, called hereinafter ZCO). The hexagonal wurtzite symmetry ZnO phase nanostructure's presence in the P63mc space group is confirmed by X-ray diffraction analyses employing Rietveld refinement. No Ca-rich clusters or separated secondary phases were observed. This assertion is supported by analyses of transmission electron microscopy (TEM) images as well as Raman spectra of ZCO taken at ambient temperature. The crystallite size and lattice strain were assessed using the Williamson-Hall (W–H) method with a variety of models, including the uniform deformation model (UDM), uniform stress deformation model (USDM), and uniform deformation energy density model (UDEDM), as well as the size-strain plot (SSP) method and morphological observations using TEM images. Magnetization (M) as a function of temperature (T) and magnetic field (H) reveal that the sample exhibits both ferromagnetic (FM) and antiferromagnetic (AFM) ordering; the M vs. T curve is well fitted by a combined equation derived from the three-dimensional (3D) spin wave model and Curie–Weiss law, which confirms the existence of a mixed state of FM and PM phases. By using the polaronic percolation of bound magnetic polarons (BMP) generated by oxygen vacancies (VO) defects, magnetic interaction may be explored and described quantitatively. [ABSTRACT FROM AUTHOR]

Charge transport studies on pulsed laser deposition grown Y0.95Ca0.05MnO3 (YCMO) thin film on (100) single crystalline Nb:SrTiO3 (SNTO) substrate. X-ray diffraction analysis reveals the single phase nature of YCMO manganite film having lattice mismatch between YCMO thin layer and SNTO substrate. Surface morphology, studied using atomic force microscopy, indicates the presence of island like grain growth with narrow size distribution. Transport properties have been studied by performing temperature dependent resistivity under different applied voltages across the YCMO/SNTO interface to understand the charge conduction across the same interface. The observed electric field-induced modifications in interface resistance across the YCMO/SNTO lattice have been discussed in the contexts of barrier between YCMO and SNTO, oxygen vacancies, structural disorder and structurally strained region at the film–substrate interface. Electrical resistance has been theoretically fitted using various models and mechanisms to better understand the charge conduction mechanisms in the semiconducting region for the YCMO/SNTO interface. [ABSTRACT FROM AUTHOR]

The study is devoted to the theoretical analysis of noncollinear magnetic structures of charge-ordered manganites with a doping level of x = 3/4, 4/5. The reasons for canted and perpendicular magnetic structures to form as a result of the competition between the orbitally dependent exchange interactions in different crystallographic directions and the influence of single-ion anisotropy are considered. The mechanism of formation of predominantly noncollinear magnetic structures is shown. Trimer stripe magnetic structures with ordering along pseudo-perovskite axes xp, yp, zp = b are predicted. The presence of magnetic structure components aligned with the b axis is assumed and methods for checking the presence of such components based on field dependencies of magnetization and antiferromagnetic resonance frequencies are proposed. [ABSTRACT FROM AUTHOR]

The crucial role of interface engineering in controlling functionality has been well documented in the (001)-orientated perovskite oxide heterostructures; however, limited attention has been given to other epitaxial orientations. In this study, the (La,Sr)MnO3 heterostructure is selected to present the epitaxial-orientation-dependent interface engineering strategies based on magnetoelectric coupling and oxygen octahedral coupling. When capped by a ferroelectric PbTiO3 layer for interlayer magnetoelectric coupling, the (001) (La,Sr)MnO3 layer exhibits the most significant magnetic modulations compared to (110) and (111) counterparts. This can be attributed to the PbTiO3's out-of-plane polarization that depends on the epitaxial orientations. Also, if considering the interfacial oxygen octahedral structure in terms of epitaxial orientations, the buffer (or cap) layer hosts the most part of interfacial oxygen octahedra and, thus, plays a dominant role in controlling oxygen octahedral coupling of (001)-orientated [or (110)-orientated] perovskite heterostructures. This is consistent with our observations that for the (001) [or (110)] (La,Sr)MnO3 heterostructures, the DyScO3 buffer layer offers the more (or less) effective magnetic modulations compared to the cap one. These findings underscore the orientation-dependent nature of interface engineering in manganite heterostructures as well as in other perovskite heterostructures for tailoring functionalities. [ABSTRACT FROM AUTHOR]

In order to study the sedimentation stability of silicone oil-based magnetorheological fluids with fumed silica as additive, magnetorheological fluids with different mass fractions of fumed silica, particle sizes of carbonyl iron powder and viscosities of silicone oil were prepared. The sedimentation rate of magnetorheological fluids was calculated by observation method, and the zero-field viscosity of magnetorheological fluids was measured by viscometer. The results show that the sedimentation rate and viscosity of magnetorheological fluids increase gradually with the increase of the mass fraction of fumed silica. The mass fraction of fumed silica should not be constant for magnetorheological fluids, but should be determined according to the content of silicone oil in magnetorheological fluids. With the increase of average diameter of carbonyl iron powder, the sedimentation stability of magnetorheological fluids becomes worse. With the increase of viscosity of silicone oil, the sedimentation stability of magnetorheological fluids does not increase significantly. However, the high viscosity of silicone oil will result in wall hanging phenomenon, and increase the start-up difficulty of magnetorheological device. With 2.5 wt% of fumed silica for silicone oil, the magnetorheological fluids has good sedimentation stability and suitable zero-field viscosity. [ABSTRACT FROM AUTHOR]

The development of magnetocaloric materials with a significantly enhanced volumetric cooling capability is highly desirable for the application of adiabatic demagnetization refrigerators in confined spatial environments. Here, the thermodynamic characteristics of a magnetically frustrated spin‐7/2 Gd9.33[SiO4]6O2 is presented, which exhibits strongly correlated spin disorder below ≈1.5 K. A quantitative model is proposed to describe the magnetization results by incorporating nearest‐neighbor Heisenberg antiferromagnetic and dipolar interactions. Remarkably, the recorded magnetocaloric responses are unprecedentedly large and applicable below 1.0 K. It is proposed that the S = 7/2 spin liquids serve as versatile platforms for investigating high‐performance magnetocaloric materials in the sub‐kelvin regime, particularly those exhibiting a superior cooling power per unit volume. [ABSTRACT FROM AUTHOR]

Polycrystalline compounds of lanthanum strontium manganite (La1-xSrxMnO3, LSMO) are widely used in electronic storage devices due to their minimal losses and electronic charge transport properties. In this study, we investigated how varying substitutions of Sr2+ for values of x = 0.0, 0.1, and 0.2 affected the tuning of the optical band gap and dielectric losses in La1-xSrxMnO3 nanoparticles. Synthesized samples were structurally analyzed via X-ray diffraction. A rhombohedral R 3ccrystal structure was confirmed for all prepared samples; crystallite size ranging from 15 nm to 20 nm was estimated along with other lattice parameters. Polygonal or hexagonal-like morphology was revealed by field emission scanning electron microscopy, with a moderate size distribution of nanoparticles affected by thinner grain boundaries in doped LSMO. Energy dispersive spectroscopy was employed to confirm the elemental composition of each compound, and the infrared spectrum indicated bonding in the fingerprint region It was observed that there was a significant reduction in the optical band gap, which was measured using ultraviolet spectrometer absorption data. The band gap decreased from 4.34 eV to 4.11 eV. This reduction was found to be related to the difference in refractive index, which was calculated using both Moss and Herve–Vandamme relations. In parallel, frequency-dependent dielectric analysis revealed that frequency was proportional to the increase in Sr content, inversely affecting dielectric loss. Moreover, the AC conductivity of the prepared samples increased with the rise in Sr content, as described by Johnscher’s universal power law in the region of high frequency. [ABSTRACT FROM AUTHOR]

Gd0.2Ca0.8MnO3 thin films were deposited on various substrate materials and their structural and resistive switching (RS) properties were investigated. The deposition resulted in epitaxial and polycrystalline films, with the latter also exhibiting distorted film surfaces. Both epitaxial and a part of polycrystalline films used as RS devices showed consistent RS performance in which an order of magnitude, or higher, switching ratios were achieved between high and low resistance states. The devices showed strong endurance during repeated switching cycles. However, under retention characterization, the resistance states did not remain distinguishable in devices constructed on polycrystalline films, while other devices maintained separable resistance states. The RS results are discussed in relation to the structural characteristics of the films, and this work helps us understand the RS mechanisms that still remain elusive in manganite-based devices. [ABSTRACT FROM AUTHOR]

A series of high entropy manganite perovskites (La 0. 2 Pr 0. 2 Nd 0. 2 Bi 0·2 Ba 0. 2)MnO 3 , (La 1/6 Pr 1/6 Gd 1/6 Bi 1/6 Sr 1/6 Ba 1/6)MnO 3 , (La 0.2 Nd 0.2 Gd 0.2 Sr 0·2 Ba 0.2)MnO 3 and (La 1/6 Pr 1/6 Nd 1/6 Ca 1/6 Sr 1/6 Ba 1/6)MnO 3 with variable hole concentration at fixed A-site ionic radius ( = 1.253 Å) have prepared by sol-gel technique. Single phase samples were characterized by the powder X-ray diffraction (PXRD), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray (EDX) analysis and elemental mapping which confirm the phase purity of the samples, surface morphology, elemental ratio and chemical homogeneity. X-ray photoelectron spectroscopic (XPS) studies reveal the increase of Mn4+ ions systematically with the substitution of hole concentration at A-site. Magnetization study in this high entropy sample with variable hole concentration at fixed = 1.253 Å exhibits several contrasting behaviour compare to the conventional hole doped samples. In these high entropy manganites the variation in critical temperature (T C) does not follow expected trend neither with the hole concentration nor to the cationic size disorder parameter, σ 2. Though the is fixed, there is a slight increase in tolerance factor (f) due to hole variation in B-site. Interestingly, T C variation with f shows similar trend to the hole concentration, which is expected to be increased linearly. The effect of f on T C is rather weaker in comparison to σ 2. The large drop in T C for high entropy system with respect to the conventional manganite is related to the local structural distortion which severely hampers the Mn3+—O—Mn4+ double exchange interaction. The competing magnetic interactions lead to magnetic phase separation as well as Griffith like phase. Spin pinning is noticed for the samples containing six elements in A-site which is independent on hole concentration. Possible spin clustering is also realized above ferromagnetic T C. Careful analysis of the magnetization data suggests that observed anomaly in magnetic behaviour can be ascribed to the local chemical disordering apart from the size disorder parameter. The possible role on magnetic properties of the number of elements occupying in a crystallographic site is emphasized. [ABSTRACT FROM AUTHOR]

Doped calcium manganite perovskites CaMnO 3− δ which constitute some of the most promising materials for all-oxide thermoelectric generators for conversion of heat to electricity operating in air over a wide temperature range have been modified by Sr–Pb–Ho co-doping. The Ca 0.5 Sr 0.45− x Pb 0.05 Ho x MnO 3− δ samples (x = 0.05, 0.10, 0.15 and 0.20) synthesized by the citrate-nitrate method of precursor preparation are shown to have an orthorhombic crystal structure (space group Pbnm) at room temperature. The relationship between temperature, concentration of donor ions, Jahn-Teller distortions and energy parameters of carrier formation and mobility that affect the thermoelectric properties of electron-doped manganites has been studied. The temperature-activated nature of the electrical conductivity (σ) was revealed to be consistent with the adiabatic mechanism of small-radius polaron transport. The increase in the absolute values of the Seebeck coefficient (S) with rising temperature and the decrease in σ above 500 K are attributed to the decrease in the concentration of Mn3+ ions due to their disproportionation into Mn2+ and Mn4+ ions. The equilibrium constants of the disproportionation reaction, carrier concentration and mobility have been derived from the temperature dependencies of S (T) and σ (T) in the conditions when δ ≈ 0. The best values of power factor (S 2 σ) and dimensionless thermoelectric figure-of-merit (ZT = S 2 σT / κ) have been found at the substitution level x = 0.15. [ABSTRACT FROM AUTHOR]

Ancient manganese (Mn) deposits are primarily characterized by the presence of Mn(II) carbonates that likely formed by the diagenetic reduction of precursor Mn(IV) oxides. As such, Precambrian sedimentary Mn deposits have been used as a line of evidence for the evolution of oxygen in Earth's surface environments. However, recent studies have shown that these Mn(II)-carbonates have the ability to directly accumulate within anoxic water columns, where free oxygen does not play a role in their formation. This alternative pathway casts uncertainty on the robustness of using ancient Mn deposits to constrain the redox fabric of the past marine water columns. Here, we investigate the Wafangzi Mn and Fe ore deposit from the 1.45 billion-year-old Tieling Formation, North China. The deposit contains Mn(II,III) mineral phases (hausmannite, braunite) as inclusions, or unreacted residues, trapped within Mn(II) carbonate (Ca-rhodochrosite). Some nodules and oolites of Mn(II) and Fe(II)-carbonate phases are also present and display a banded structure with concentric rings. Mn(III) oxide (manganite) is present in a paragenetic assemblage along with hematite and replacement textures with braunite. The negative carbon isotope composition (δ13C, –7‰ to –4‰) from Mn(II) carbonate samples in the Wafangzi Mn deposit which are distinct from that of contemporaneous seawater (~0‰), along with petrographic and speciation analyses, collectively suggest that the Mn(II,III)- and Fe(II)-bearing mineral phases formed through the diagenetic reduction of primary Mn(IV)/Fe(III) minerals coupled to the oxidation of organic matter. Therefore, the Wafangzi Mn deposit suggests the presence of sufficiently oxygenated marine waters, overlying anoxic ferruginous deeper waters with a transitional manganous water layer that could have driven the redox cycling of Mn, Fe, and C. Given the contemporaneous economic Mn deposits in the 1.45 Ga Ullawarra Formation in Western Australia, our findings imply the existence of a transient, and perhaps widespread, pulsed oxygenation event in the mid-Proterozoic oceans. [ABSTRACT FROM AUTHOR]

In this study, glucose oxidase (GOD) was fixed on ferrimagnetic vortex-domain iron oxide nanorings (FVIOs) using the covalent bond crosslinking method to create FVIOs-GOD compounds. The activity of surface-conjugated enzymes can be effectively and selectively enhanced by utilizing FVIOs to induce magnetothermal effects under the influence of alternating magnetic fields. GOD can further catalyze the oxidation of glucose to hydrogen peroxide (H2O2), which possesses bactericidal properties. This study presents a comprehensive technique for controlling the activity of enzymes by nano-magnetothermal stimulation, which was utilized in Escherichia coli antibacterial studies. In comparison to the control group, the enzyme activity of the FVIOs-GOD immobilized enzymes rose by 50 % due to the nano-magnetothermal stimulation, and the enzyme activity could be controlled by varying the magnetic field intensity. The antibacterial experiments indicated that the survival rate of Escherichia coli decreased by 55 % after exposure to a magnetic field. [ABSTRACT FROM AUTHOR]

In this work, the enhancement of the magnetocaloric effect by mixing different alkaline-earth-doped lanthanum manganites is reported. The sintering process of the mixed manganites promotes the unexpected presence of a strontium–calcium-co-doped lanthanum manganite phase that enhances the magnetocaloric properties of the composite. Consistent with this result, the composite shows three Curie temperatures at 263 K, 309 K, and 284 K, attributed to the three different phases found. The transition was identified as a second-order phase transition by the Arrott plots. A maximum entropy change of 11.66 J·(kg·K)−1 was obtained for the composite at 18 kOe. It corresponds to a refrigeration cooling power of 484.98 J·kg−1 near room temperature. The results demonstrated the synergistic contribution to the magnetocaloric properties of individual phases, enhancing the magnetocaloric effect by obtaining a composite. [ABSTRACT FROM AUTHOR]

Understanding magnetotransport properties in semiconductors plays a vital role in either developing future spintronic or unveiling the underpinning physics of electronic dynamics. In recent years, the high‐field magnetoconductance (HFM, B ~ 1 T) in polymers has drawn intense discussions and always been attributed to thermal spin polarization (TSP). In this work, the HFMs in several benchmark polymers are proposed to be correlated to the ∆g spin‐mixing effect, determined from their remarkable anisotropy in response to magnetic fields, which cannot be explained only by TSP. It is the fundamental difference between two spins' Lande factors stemming from the random orientations of molecular backbones that contributes to the intense ∆g spin‐mixing effect, leading to HFMs' anisotropy as high as 150%. It is further found that the ∆g spin‐mixing mechanism greatly correlates with the charge transport dynamics in polymers, in which a slow‐ to fast‐hopping crossover was observed and further verified by pressure‐dependent HFMs characteristics. [ABSTRACT FROM AUTHOR]

We have investigated in this work the presence of a possible correlation between electrical and magnetic properties in Pr0.7Sr0.25MnO3 lacunar compound synthesized by solid-state reaction. The temperature dependence of electrical resistivity ρ (T) shows a metal–insulator transition at T ρ = 207 K. The phenomenological percolation model, based on the segregation of ferromagnetic metallic phases and paramagnetic insulating regions, was successfully used in order to fit the electrical resistivity in the vicinity of the electrical transition temperature. The studied sample exhibits a strong correlation between electrical and magnetic properties. Such correlation was exploited to evaluate the evolution of temperature dependent magnetic entropy change from the isothermal resistivity measurements. The percolative nature of the electrical/magnetic transition can be a possible origin of the colossal magnetoresistive effect observed near T ρ . [ABSTRACT FROM AUTHOR]

The samples with A‐site cation ordering Ba1−x/2Ti1−xNbxO3 (BTN) with 0 ≤ x ≤ 0.010 were synthesized via the conventional ceramic route by calcining at 1200°C and sintered at 1350°C. The preliminary study of the phase of prepared samples was determined through X‐ray diffraction (XRD) analysis. The Rietveld refinement analysis indicates the tetragonal phase in BTN0 sample, whereas the doped samples exhibit a combination of tetragonal and cubic phases. Presence of Raman band at 308 cm−1 suggests the presence of tetragonal in all samples. The dielectric constant was observed to be 1500 (BTN0), 3000 (BTN5) and 1680 (BTN10) while tangent loss found 0.6 (BTN0), 0.04 (BTN5) and 0.07 (BTN10). All the sample shows same Curie temperature (120°C) due to Ba‐site cation ordering in the sample. Ferroelectric nature in all samples was also confirmed by modified Curie‐Weis law. Based on the current studies, the present materials can be explored as a potential candidate for ferroelectric‐memory devices, dielectric capacitor and energy harvesting applications. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental studies of the cross section of the interfaces of the SrIrO3/La0.7Sr0.3MnO3 and Pt/La0.7Sr0.3MnO3, heterostructures, in which, upon excitation of ferromagnetic resonance in a La0.7Sr0.3MnO3 film, a spin current arises that flows through the interface in structure. Epitaxial growth of thin films of strontium iridate SrIrO3 and manganite La0.7Sr0.3MnO3 on a (110)NdGaO3 single-crystal substrate was carried out using magnetron sputtering at a high temperature in a mixture of argon and oxygen gases. The spin mixing conductance, which determines the amplitude of the spin current and generally has real Re g↑↓ and imaginary Im g↑↓ parts, was determined from the frequency dependence of the FMR spectrum of the La0.7Sr0.3MnO3 film and the heterostructures. It is shown that the Im g↑↓ quantity can play an important role in determining the spin Hall angle (θSH) from the angular dependence of the spin magnetoresistance. For the SrIrO3/La0.7Sr0.3MnO3 heterostructures, θSH turns out to be significantly higher (almost an order of magnitude) than that for the Pt/La0.7Sr0.3MnO3 heterostructure. [ABSTRACT FROM AUTHOR]

The mixed-valence perovskite manganites attracted much attention because of their interesting electro-magnetic properties, and strain modulation on magnetic properties of perovskite manganites is worth exploring. In this paper, [La 0. 8 Ca 0. 2 MnO3/La 0. 5 Ca 0. 5 MnO3] 2 0 superlattice films with different La 0. 8 Ca 0. 2 MnO3 layer thicknesses are prepared by pulsed laser deposition (PLD). The crystal structures (lattice constants) of samples are measured by X-ray diffraction (XRD). The strain of the films is determined according to their crystal structures. The magnetic hysteresis loops (M-H loops) and magnetization versus temperature (M-T) curves of these superlattice films are measured by the physical property measurement system (PPMS). From the M-H loops, the coercive field (H C) of the samples can be measured. From the M-T curves, the Curie temperature (T C) of the samples can be obtained. All samples show a ferromagnetic to paramagnetic transition at TC, and the [La 0. 8 Ca 0. 2 MnO3/La 0. 5 Ca 0. 5 MnO3] 2 0 sample with the La 0. 8 Ca 0. 2 MnO3 layer thicknesses of 72 Å has an antiferromagnetic Néel transition at TN. According to the strain state and magnetic phases, the magnetic properties are comprehensively analyzed. It is found that with the increase of ferromagnetic La 0. 8 Ca 0. 2 MnO3 layer thickness, the ferromagnetic phase is increased, and the double exchange effect can also be enhanced, resulting in the increase of TC. When the thickness of La 0. 8 Ca 0. 2 MnO3 reaches 96 Å, the uneven strain distribution in the superlattice can induce the reduction of ferromagnetic phase compared with antiferromagnetic phase (even antiferromagnetic phase starts to appear), and the double exchange effect can be weakened, and finally leading to the decrease of TC. In addition, with increasing the La 0. 8 Ca 0. 2 MnO3 layer thickness, HC gradually decreases. The change of HC is related to strain states and magnetic phase interactions in the samples. The analysis of the strain and magnetism can contribute to the understanding of perovskite manganite superlattice films. [ABSTRACT FROM AUTHOR]

In correlated oxides, collaborative manipulation on light intensity, wavelength, pulse duration and polarization has yielded many exotic discoveries, such as phase transitions and novel quantum states. In view of potential optoelectronic applications, tailoring long-lived static properties by light-induced effects is highly desirable. So far, the polarization state of light has rarely been reported as a control parameter for this purpose. Here, we report polarization-dependent metal-to-insulator transition (MIT) in phase-separated manganite thin films, introducing a new degree of freedom to control static MIT. Specifically, we observed giant photoinduced resistance jumps with striking features: (1) a single resistance jump occurs upon a linearly polarized light incident with a chosen polarization angle, and a second resistance jump occurs when the polarization angle changes; (2) the amplitude of the second resistance jump depends sensitively on the actual change of the polarization angles. Linear transmittance measurements reveal that the origin of the above phenomena is closely related to the coexistence of anisotropic micro-domains. Our results represent a first step to utilize light polarization as an active knob to manipulate static phase transitions, pointing towards new pathways for nonvolatile optoelectronic devices and sensors. [ABSTRACT FROM AUTHOR]

The interplay among various order parameters in quantum materials frequently results in exotic ground states and may facilitate revolutionary functional control. In the A-site-ordered manganite double perovskite SmBaMn2O6, it was demonstrated that an anisotropic strain of less than 0.1% can modulate electrical transport by over 6% near the Neel temperature. It is hypothesized that this phenomenon is due to the high sensitivity of spin fluctuation near the antiferromagnetic ordering to lattice distortion, resulting in significant changes in transport properties. This study offers a compelling approach for investigating the interaction between the electric properties of SmBaMn2O6 and in situ anisotropic strain. [ABSTRACT FROM AUTHOR]

This document is an introduction to the topic of innovative nanomaterial properties and applications in chemistry, physics, medicine, and the environment. It discusses the importance of controlling and designing nanomaterials with specific properties and highlights the interdisciplinary nature of nanomaterial research. The document also mentions the most explored types of nanomaterials, such as metallic-based and carbon-based nanomaterials, and their various applications in fields like biosensors, drug delivery, and water decontamination. Additionally, it provides a summary of 12 original research papers included in a special issue on nanomaterial synthesis and characterization. The document concludes by expressing gratitude to the authors and reviewers who contributed to the special issue. [Extracted from the article]