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© 2019 Trans Tech Publications, Switzerland. 0.85La0.7 Sr0.3 MnO3 /0.15GeO2 composite material and pure La0.7 Sr0.3 MnO3 were investigated by X-ray diffraction, scanning electron microscopy, magnetometry and electron spin resonance methods. It was observed that both samples demonstrate the ferromagnetic properties, while the absolute value of the magnetization, the magnetic entropy change and the magnetic ordering temperature decrease in composite in comparison with pure La0.7 Sr0.3 MnO3 . The electron spin resonance spectra of investigated (1-x)La0.7 Sr0.3 MnO3 /xGeO2 (x=0, 0.15) can be attributed to the superposition of electron spin resonance spectra from magnetically anisotropic particles with different orientations.

© 2016, Pleiades Publishing, Inc.New composite materials (SrFe12O19)x(CaCu3Ti4O12)1–x (x = 0, 0.05, 1) have been synthesized. Their magnetic properties are studied in the temperature range 5–300 K using the magnetic resonance and magnetometry methods. It is found that strontium hexaferrite microinclusions in the (SrFe12O19)0.05(CaCu3Ti4O12)0.95 composite “magnetize” CaCu3Ti4O12 at temperatures from 300 to 200 K, forming a ferrimagnetic particle near the SrFe12O19 “core.” The magnetic resonance line below 200 K splits into two lines corresponding to SrFe12O19 and CaCu3Ti4O12. The core effect decoration is manifested in the increase in the Curie–Weiss temperature from 25 K in CaCu3Ti4O12 without the doping ceramics to 80 K in the composite with 5% of SrFe12O19.

© 2017 Elsevier B.V. (La 0.7 Sr 0.3 MnO 3 ) x (CaCu 3 Ti 4 O 12 ) 1−x (0.01 ≤ x ≤ 0.3) nanostructured composites with La 0.7 Sr 0.3 MnO 3 (LSMO) microinclusions in CaCu 3 Ti 4 O 12 (CCTO) matrix were synthesized using a solid state method. The structural and microstructural details were studied by X-ray diffraction (XRD), X-ray fluorescence (XFA), scaning electron microscope (SEM) and transmission electron microscope (TEM) techniques. The magnetic properties were studied by electron spin resonance (ESR) and magnetometry methods. In the concentration range 0.01 < x < 0.1 physical properties of composites differ from the properties of the individual components CCTO or LSMO. The Curie temperature of the ferromagnetic phase for all concentrations is T C = 315 K, that is less at 50 K than in pure LSMO. The Weiss constant of the paramagnetic phase has the strong concentration dependance. The observed mutual influence on the magnetic properties of both components can be tentatively attributed to the interface exchange interactions between them, hinting a possible magnetic proximity effect.

© 2017 Elsevier B.V. (La 0.7 Sr 0.3 MnO 3 ) x (CaCu 3 Ti 4 O 12 ) 1−x (0.01 ≤ x ≤ 0.3) nanostructured composites with La 0.7 Sr 0.3 MnO 3 (LSMO) microinclusions in CaCu 3 Ti 4 O 12 (CCTO) matrix were synthesized using a solid state method. The structural and microstructural details were studied by X-ray diffraction (XRD), X-ray fluorescence (XFA), scaning electron microscope (SEM) and transmission electron microscope (TEM) techniques. The magnetic properties were studied by electron spin resonance (ESR) and magnetometry methods. In the concentration range 0.01 < x < 0.1 physical properties of composites differ from the properties of the individual components CCTO or LSMO. The Curie temperature of the ferromagnetic phase for all concentrations is T C = 315 K, that is less at 50 K than in pure LSMO. The Weiss constant of the paramagnetic phase has the strong concentration dependance. The observed mutual influence on the magnetic properties of both components can be tentatively attributed to the interface exchange interactions between them, hinting a possible magnetic proximity effect.

© 2016, Pleiades Publishing, Inc.New composite materials (SrFe12O19)x(CaCu3Ti4O12)1–x (x = 0, 0.05, 1) have been synthesized. Their magnetic properties are studied in the temperature range 5–300 K using the magnetic resonance and magnetometry methods. It is found that strontium hexaferrite microinclusions in the (SrFe12O19)0.05(CaCu3Ti4O12)0.95 composite “magnetize” CaCu3Ti4O12 at temperatures from 300 to 200 K, forming a ferrimagnetic particle near the SrFe12O19 “core.” The magnetic resonance line below 200 K splits into two lines corresponding to SrFe12O19 and CaCu3Ti4O12. The core effect decoration is manifested in the increase in the Curie–Weiss temperature from 25 K in CaCu3Ti4O12 without the doping ceramics to 80 K in the composite with 5% of SrFe12O19.