Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass exhibited excellent magnetic refrigeration material with a wide temperature range and high refrigeration capacity(RC)was reported.Er_(20)Ho_(20)Dy_(20)Cu_...Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass exhibited excellent magnetic refrigeration material with a wide temperature range and high refrigeration capacity(RC)was reported.Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass was observed with typical spin glass behavior around 15.5 K.In addition,we find that the magnetic entropy change(-△S_(M))originates from the sample undergoing a ferromagnetic(FM)to paramagnetic(PM)transition around 20 K.Under a field change from 0 T to 7 T,the value of maximum magnetic entropy change(-△S_(M)^(max))reaches 12.5 J/kg·K,and the corresponding value of RC reaches 487.7 J/kg in the temperature range from 6 K to 60 K.The large RC and wide temperature range make the Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass be a promising material for application in magnetic refrigerators.展开更多
Antiferromagnetic LiErF4has attracted extensive attention due to its dipolar interaction domination and quantum fluctuations action. In the present work, the crystal structure, cryogenic magnetic properties, and magne...Antiferromagnetic LiErF4has attracted extensive attention due to its dipolar interaction domination and quantum fluctuations action. In the present work, the crystal structure, cryogenic magnetic properties, and magnetocaloric effect(MCE) of polycrystalline LiErF4compound are investigated. Crystallographic study shows that the compound crystallizes in the tetragonal scheelite structure with I41/a space group. It exhibits an antiferromagnetic(AFM) phase transition around 0.4 K, accompanied by a giant cryogenic MCE. At 1.3 K, the maximum values of magnetic entropy changes are 24.3 J/kg·K,33.1 J/kg·K, and 49.0 J/kg·K under the low magnetic field change of 0–0.6 T, 0–1 T, and 0–2 T, respectively. The giant MCE observed above Néel temperature TNis probably due to the strong quantum fluctuations, which cause a large ratio of the unreleased magnetic entropy existing above the phase transition temperature. The outstanding low-field MCE below 2 K makes the LiErF4compound an attractive candidate for the magnetic refrigeration at the ultra-low temperature.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52371203 and 52271192)the Ministry of Science and Technology of China(Grant No.2021YFB3501201)。
文摘Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass exhibited excellent magnetic refrigeration material with a wide temperature range and high refrigeration capacity(RC)was reported.Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass was observed with typical spin glass behavior around 15.5 K.In addition,we find that the magnetic entropy change(-△S_(M))originates from the sample undergoing a ferromagnetic(FM)to paramagnetic(PM)transition around 20 K.Under a field change from 0 T to 7 T,the value of maximum magnetic entropy change(-△S_(M)^(max))reaches 12.5 J/kg·K,and the corresponding value of RC reaches 487.7 J/kg in the temperature range from 6 K to 60 K.The large RC and wide temperature range make the Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass be a promising material for application in magnetic refrigerators.
基金supported by the National Science Fund for Distinguished Young Scholars of China (Grant No. 51925605)the National Natural Science Foundation of China (Grant No. 52171195)+2 种基金the Key Research Program of the Chinese Academy of Sciences (Grant No. ZDRW-CN-2021-3)the Basic Frontier Scientific Research Program of Chinese Academy of Sciences From 0 to 1 Original Innovation Project (Grant No. ZDBS-LY-JSC017)the Scientific Instrument Developing Project of Chinese Academy of Sciences (Grant No. YJKYYQ20200042)。
文摘Antiferromagnetic LiErF4has attracted extensive attention due to its dipolar interaction domination and quantum fluctuations action. In the present work, the crystal structure, cryogenic magnetic properties, and magnetocaloric effect(MCE) of polycrystalline LiErF4compound are investigated. Crystallographic study shows that the compound crystallizes in the tetragonal scheelite structure with I41/a space group. It exhibits an antiferromagnetic(AFM) phase transition around 0.4 K, accompanied by a giant cryogenic MCE. At 1.3 K, the maximum values of magnetic entropy changes are 24.3 J/kg·K,33.1 J/kg·K, and 49.0 J/kg·K under the low magnetic field change of 0–0.6 T, 0–1 T, and 0–2 T, respectively. The giant MCE observed above Néel temperature TNis probably due to the strong quantum fluctuations, which cause a large ratio of the unreleased magnetic entropy existing above the phase transition temperature. The outstanding low-field MCE below 2 K makes the LiErF4compound an attractive candidate for the magnetic refrigeration at the ultra-low temperature.
