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    Magnetocaloric properties of multicomponent Laves phase compounds and their composites
    (Bristol : IOP Publ., 2021) Ćwik, J.; Koshkid’ko, Yu; Nenkov, K.; Kolchugina, N.
    Heat capacity measurements have been performed for multicomponent (Ho0.9Er0.1)1-xGdxCo2 compounds with x = 0.05, 0.1, and 0.15. The isothermal magnetic entropy change, ΔSmag, allowing the estimation of the magnetocaloric effect, was determined based on the heat capacity measurements in magnetic fields up to 2 T. A numerical method, with the magnetic entropy change of individual (Ho0.9Er0.1)1-xGdxCo2 compounds, was used to calculate the optimal molar composition of the constituents and the resulting change of the isothermal magnetic entropy of composite, ΔScomp. The results show that proposed composite can be considered as a refrigerant material in magnetic refrigerators performing an Ericsson cycle in a temperature range of 90-130 K.
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    Improved accuracy in high-frequency AC transport measurements in pulsed high magnetic fields
    ([S.l.] : American Institute of Physics, 2020) Mitamura, Hiroyuki; Watanuki, Ryuta; Kampert, Erik; Förster, Tobias; Matsuo, Akira; Onimaru, Takahiro; Onozaki, Norimichi; Amou, Yuta; Wakiya, Kazuhei; Yamamoto, Isao; Matsumoto, Keisuke T.; Suzuki, Kazuya; Zherlitsyn, Sergei; Wosnitza, Joachim; Tokunaga, Masashi; Kindo, Koichi; Sakakibara, Toshiro
    We show theoretically and experimentally that accurate transport measurements are possible even within the short time provided by pulsed magnetic fields. For this purpose, a new method has been devised, which removes the noise component of a specific frequency from the signal by taking a linear combination of the results of numerical phase detection using multiple integer periods. We also established a method to unambiguously determine the phase rotation angle in AC transport measurements using a frequency range of tens of kilohertz. We revealed that the dominant noise in low-frequency transport measurements in pulsed magnetic fields is the electromagnetic induction caused by mechanical vibrations of wire loops in inhomogeneous magnetic fields. These results strongly suggest that accurate transport measurements in short-pulsed magnets are possible when mechanical vibrations are well suppressed. © 2020 Author(s).