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A chiral soliton lattice (CSL) is a topological spin-texture that has potential applications in next-generation spintronic devices. In this work, we performed angle-dependence of magnetization and electron spin resonance (ESR) investigations on the CSL host Yb(Ni1−xCux)3Al9 with x = 0.06 (YNCA). The angle-dependent magnetization reveals a peculiar variable magnetic anisotropy. The maximum magnetization axis is parallel to the ab-plane below the field of ∼35.7 kOe while shifts to the c-axis at higher fields. The microwave responses of the CSL helicoid and ferromagnetic resonance (FMR) of the forced ferromagnetic state (FFM) are observed and appear as two resonance lines on ESR spectra with the highest intensities in the ab-plane. When the external field is rotated from H ⊥ c to H / / c , the resonance field H r 1 corresponding to the CSL helicoid decreases while H r 2 correlated with the FMR increases. Furthermore, the temperature-dependent ESR shows that the CSL persists until 15 K much higher than TC (6.4 K), which suggests a precursor phenomenon. The microwave response in YNCA provides a powerful tool for modulating and researching the CSL. [ABSTRACT FROM AUTHOR]

A mononuclear five‐coordinate Cu(II) complex [Cu(12‐TMC)Cl][B(C6H5)4] (1) (12‐TMC = 1,4,7,10‐tetramethyl‐1,4,7,10‐tetraazacyclododecane) with distorted square pyramidal geometry has been synthesized and characterized by single‐crystal X‐ray diffraction, direct‐current and alternating‐current magnetic measurements and electron paramagnetic resonance (EPR) spectroscopy. The complex displays slow magnetic relaxation under an external dc field. The analysis of the field‐ and temperature‐dependence of the relaxation rates suggests that the slow dynamics of the magnetization is dominated by the Raman‐like process in the temperature range of 1.8 K to 11 K under an applied dc field of 0.15 T. In addition, the results of magnetic dynamics for the diluted sample with diamagnetic Zn(II) ions confirms the molecular origin of slow magnetic relaxation. [ABSTRACT FROM AUTHOR]

Co3Sn2S2, a quasi-two-dimensional system with a kagome lattice, has been found to be a magnetic Weyl semimetal recently. In this work, the anisotropies of magnetization and transport properties of Co3Sn2S2 were investigated. The high field measurements reveal a giant magnetocrystalline anisotropy with an out-of-plane saturation field of 0.9 kOe and an in-plane saturation field of 230 kOe at 2 K, showing a magnetocrystalline anisotropy coefficient Ku up to 8.3 × 105 J m−3, which indicates that it is extremely difficult to align the small moment of 0.29 μB/Co on the kagome lattice from the c axis to the ab plane. The out-of-plane angular dependence of Hall conductivity further reveals strong anisotropies in the Berry curvature and ferromagnetism, and the vector directions of both are always parallel with each other. For the in-plane situation, the longitudinal and transverse measurements for both I // a and I ⊥ a cases show that the transport on the kagome lattice is isotropic. These results provide the essential understanding of the magnetization and transport behaviors for the magnetic Weyl semimetal, Co3Sn2S2. [ABSTRACT FROM AUTHOR]

The magnetism and electronic transport properties of $$\hbox {La}_{0.6}\hbox {A}_{0.1}\hbox {Sr}_{0.3}\hbox {MnO}_{3}$$ (A = Sm, Dy, Er) are studied by the measurements of magnetization and resistivity. Infrared spectra reveal that two typical absorbed peaks occur in their corresponding positions. However, the stretching mode $$\nu _{3}$$ exhibits an obvious shift to low frequency and its intensity gets enhanced in Dy- and Er-doping samples. In Raman spectra, the stretching mode shows the same shift, while the Jahn-Teller mode remains invariant. The A-site substitution with other elements changes the average ionic radius and induces cation disorder, causing a decrease of the Curie temperature and the formation of spin-cluster-glass. Except for Sm-doping sample, the field dependence of magnetization at different temperatures shows a similar magnetization process indicating that the low concentration substitution with 10 % magnetic ions cannot signally influence the magnetic exchange interaction on B-site sublattice. Based on the analysis of electronic transport in metallic regime, we find that the main factor for impacting the electronic transport is from the variation of crystal lattice and the induced cationic disorder, regardless of magnetic or non-magnetic substitution. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper, we report the bulk magnetization, electron-spin-resonance spectra and transport properties of Y2Ir2O7. It is found that Y2Ir2O7 exhibits a magnetic transition at T c =150K and coexistence of antiferromagnetic and ferromagnetic component due to geometrical frustration. The antiferromagnetic order is due to Ir–O–Ir superexchange interactions and the ferromagnetic component is caused by canting of the moments from the antiferromagnetic state. The behavior of spin dynamics confirms that antiferromagnetic ordering with all-in/all-out structure is responsible for the existence of ferromagnetic component. The resistivity reveals that this compound is a semiconductor and the variable-range hopping process dominates the transport mechanism. [Copyright &y& Elsevier]

Abstract: In this paper, the reason for choosing dopant Dy with large magnetic moment in La0.67-xDyxSr0.33MnO3 is to investigate how the magnetic structure of the system changes with Dy content increasing. It is found that all samples () undergo the transition from paramagnetism to ferromagnetism at TC. When TTC are determined by the phase separation for x=0.2 and by the Dy–O–Dy in La–O plane for x=0.3, respectively. The large magnetoresistance is caused by the sum of the applied and internal magnetic field. [Copyright &y& Elsevier]

Publisher's Note: "On the anisotropies of magnetization and electronic transport of magnetic Weyl semimetal Co3Sn2S2" [Appl. Phys. This article was originally published online on 22 November 2019 with minor grammatical errors. All online versions of the article were corrected on 25 November 2019; the article is correct as it appears in the printed version of the journal. [Extracted from the article]

The magnetic states of the BaFe2-xCoxAs2 single crystal samples have been studied by magnetization and electron spin resonance measurements. We find a transformation of the Fe2+ spin state from high temperature high-spin state to low temperature low-spin state, indicating a small crystal field splitting energy. In the superconducting samples, both the magnetization and electron spin resonance results suggest an itinerant behavior of the system. [ABSTRACT FROM AUTHOR]

A chiral soliton lattice (CSL) is a topological spin-texture that has potential applications in next-generation spintronic devices. In this work, we performed angle-dependence of magnetization and electron spin resonance (ESR) investigations on the CSL host Yb(Ni1−xCux)3Al9 with x = 0.06 (YNCA). The angle-dependent magnetization reveals a peculiar variable magnetic anisotropy. The maximum magnetization axis is parallel to the ab-plane below the field of ∼35.7 kOe while shifts to the c-axis at higher fields. The microwave responses of the CSL helicoid and ferromagnetic resonance (FMR) of the forced ferromagnetic state (FFM) are observed and appear as two resonance lines on ESR spectra with the highest intensities in the ab-plane. When the external field is rotated from H ⊥ c to H / / c , the resonance field H r 1 corresponding to the CSL helicoid decreases while H r 2 correlated with the FMR increases. Furthermore, the temperature-dependent ESR shows that the CSL persists until 15 K much higher than TC (6.4 K), which suggests a precursor phenomenon. The microwave response in YNCA provides a powerful tool for modulating and researching the CSL. [ABSTRACT FROM AUTHOR]

Co3Sn2S2, a quasi-two-dimensional system with a kagome lattice, has been found to be a magnetic Weyl semimetal recently. In this work, the anisotropies of magnetization and transport properties of Co3Sn2S2 were investigated. The high field measurements reveal a giant magnetocrystalline anisotropy with an out-of-plane saturation field of 0.9 kOe and an in-plane saturation field of 230 kOe at 2 K, showing a magnetocrystalline anisotropy coefficient Ku up to 8.3 × 105 J m−3, which indicates that it is extremely difficult to align the small moment of 0.29 μB/Co on the kagome lattice from the c axis to the ab plane. The out-of-plane angular dependence of Hall conductivity further reveals strong anisotropies in the Berry curvature and ferromagnetism, and the vector directions of both are always parallel with each other. For the in-plane situation, the longitudinal and transverse measurements for both I // a and I ⊥ a cases show that the transport on the kagome lattice is isotropic. These results provide the essential understanding of the magnetization and transport behaviors for the magnetic Weyl semimetal, Co3Sn2S2. [ABSTRACT FROM AUTHOR]

In this study, we investigated the structural, magnetic phase transition, and magnetocaloric properties of bilayer perovskite manganite La 1.38 Sr 1.62 Mn 2 O 7 based on X-ray diffraction, electron paramagnetic resonance, and temperature-/magnetic field-dependent magnetization measurements. The structural characterization results showed the prepared sample had a tetragonal structure with the space group I 4/ mmm . The Curie temperature was determined as 114 K in the magnetization studies and a second-order paramagnetic-ferromagnetic transition was confirmed by the Arrott plot, which showed that the slopes were positive for all the curves. According to the variation in the electron paramagnetic resonance spectrum, we detected obvious electronic phase separation across a broad temperature range from 220 to 80 K in this magnetic material, thereby indicating that the paramagnetic and ferromagnetic phases coexist above as well as below the Curie temperature. Based on a plot of the isothermal magnetization versus the magnetic applied field, we deduced the maximum magnetic entropy change, which only reached 1.89 J/kg.K under an applied magnetic field of 7.0 T. These theoretical investigations indicated that in addition to the magnetoelastic couplings and electron interaction, electronic phase separation and anisotropic exchange interactions also affect the magnetic entropy changes in this bilayer manganite. [ABSTRACT FROM AUTHOR]

The magnetic ions Cu2+ compose a distorted Kagome lattice. A 1/3-like magnetization plateau are observed via pulsed high-field magnetization measurement. [Display omitted] • The staircase kagome-lattice compound Cu 3 Bi(TeO 3) 2 O 2 Cl have been synthesized and it crystalizes in a space group Pnma , different from the previous report of Pcnm. • The sample experiences a long-range antiferromagnetic ordering at T 1 = 41.6 K and a short-range ordering at T 2 = 5.6 K. • A 1/3-like magnetization plateau above 18 T to at least 30 T and a field-induced magnetic transition at 3.1 T were observed. We have synthesized the single crystals of a spin-1/2 staircase kagome lattice compound Cu 3 Bi(TeO 3) 2 O 2 Cl via a solid-state reaction. This compound crystallizes in the orthorhombic crystal system with space group Pnma. The magnetic susceptibility, specific heat and ESR measurements show that the compound undergoes an antiferromagnetic ordering at T 1 = 41.6 K and a short-range ordering at T 2 = 5.6 K. The Curie-Weiss temperature is about θ CW = − 20.8 K and frustration factor f = 0.5. The magnetization curve at 2 K presents a field-induced magnetic transition at H c1 = 3.1 T, followed by a magnetization plateau with its magnetization close to 1/3 of the saturation value. Thus, Cu 3 Bi(TeO 3) 2 O 2 Cl is an weakly frustrated staircase kagome-lattice antiferromagnet exhibiting a 1/3-like magnetization plateau. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic properties of polycrystalline sample Sr2IrO4 have been investigated by the magnetization, electron magnetic resonance (EMR), the infrared (IR) and Raman spectra measurements. Our experimental results indicate that the magnetism is determined by the effective total angular moment instead of the spin with S=1/2. The temperature dependence of macromagnetic moment, resonance field of EMR line, A 2u mode of IR and mode of Raman spectra exhibit interesting behavior at about 40K. Due to the Dzyaloshinskii–Moriya interaction, the magnetic order is canted, and the ferromagnetic component decreases with decreasing temperature. These complex magnetic behaviors in the system are attributed to the change of Ir–O–Ir bond angle with cooling, while the variation of bond angle is observed through the IR and Raman spectra. [Copyright &y& Elsevier]

Abstract: In the present work, the magnetic entropy change of the half-doped Nd0.5Ca0.25Sr0.25MnO3 manganite has been investigated. The measurement of isothermal magnetization around Curie temperature reveals the maximum isothermal magnetic entropy change of 1.85 and 0.77J/kgK for and 1.0T magnetic field variation, respectively. In addition, from the data of heat capacity, we find the adiabatic temperature change of 0.88K for a magnetic field variation of 3.0T. Though only a moderate magnetic entropy change and a small adiabatic temperature change were obtained, a considerable large relative cooling power (140J/kg as ) and a wide temperature range (74K as ) were found in this sample, this ensure it to be a promising candidate for the actual magnetic refrigerant materials. [Copyright &y& Elsevier]