We conduct a detailed examination of the magnetic and electrical transport properties in GdAlSi and SmAlGe crystals,which possess a LaPtSi-type structure(space group I4_(1)md).The magnetic susceptibility data unambigu...We conduct a detailed examination of the magnetic and electrical transport properties in GdAlSi and SmAlGe crystals,which possess a LaPtSi-type structure(space group I4_(1)md).The magnetic susceptibility data unambiguously reveal magnetic ordering below a characteristic transition temperature(T_(N)).For GdAlSi,a hysteresis loop is observed in the magnetization and magnetoresistance curves within the ab plane when the magnetic field is applied below T_(N),which is around32 K.Notable specific heat anomalies are detected at 32 K for GdAlSi and 6 K for SmAlGe,confirming the occurrence of magnetic transitions.In addition,the extracted magnetic entropy at high temperatures is consistent with the theoretical value of Rln(2J+1) for J=7/2 in Gd^(3+) and J=5/2 in Sm^(3+),respectively.SmAlGe also exhibits Schottky-like specific heat contributions.Additionally,both GdAlSi and SmAlGe exhibit positive magnetoresistance and a normal Hall effect.展开更多
Magnetic materials with noncollinear spin configurations have engendered significant interest in condensed matter physics due to their intriguing physical properties.We direct our attention towards the magnetic proper...Magnetic materials with noncollinear spin configurations have engendered significant interest in condensed matter physics due to their intriguing physical properties.We direct our attention towards the magnetic properties and critical behavior of single-crystal SmMn_(2)Ge_(2),an itinerant magnet with numerous temperature-dependent magnetic phase transitions.Notably,SmMn_(2)Ge_(2)displays significant magnetic anisotropy with easy magnetization direction switching from the c axis to the ab plane as temperature decreases.The critical behavior of the ferromagnetic transition occurring above room temperature is thoroughly examined.Reliable and self-consistent critical exponents,includingβ=0.292(2),γ=0.924(8),andδ=4.164(6),along with the Curie temperature T_c=347 K,are extracted through various methods,which provide evidence for the coexistence of multiple magnetic interactions in SmMn_(2)Ge_(2).Further analysis reveals that the magnetic interaction of SmMn_(2)Ge_(2)is a long-range type with the interaction distance decaying as J(r)~r^(-4.35).展开更多
基金supported by the National Natural Science Foundation of China(Grant No.12074425)the National Key R&D Program of China(Grant No.2019YFA0308602)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Research Funds of Renmin University of China(Grant No.23XNKJ22)。
文摘We conduct a detailed examination of the magnetic and electrical transport properties in GdAlSi and SmAlGe crystals,which possess a LaPtSi-type structure(space group I4_(1)md).The magnetic susceptibility data unambiguously reveal magnetic ordering below a characteristic transition temperature(T_(N)).For GdAlSi,a hysteresis loop is observed in the magnetization and magnetoresistance curves within the ab plane when the magnetic field is applied below T_(N),which is around32 K.Notable specific heat anomalies are detected at 32 K for GdAlSi and 6 K for SmAlGe,confirming the occurrence of magnetic transitions.In addition,the extracted magnetic entropy at high temperatures is consistent with the theoretical value of Rln(2J+1) for J=7/2 in Gd^(3+) and J=5/2 in Sm^(3+),respectively.SmAlGe also exhibits Schottky-like specific heat contributions.Additionally,both GdAlSi and SmAlGe exhibit positive magnetoresistance and a normal Hall effect.
基金the National Natural Science Foundation of China(Grant Nos.12074425 and 11874422)the National Key R&D Program of China(Grant No.2019YFA0308602)。
文摘Magnetic materials with noncollinear spin configurations have engendered significant interest in condensed matter physics due to their intriguing physical properties.We direct our attention towards the magnetic properties and critical behavior of single-crystal SmMn_(2)Ge_(2),an itinerant magnet with numerous temperature-dependent magnetic phase transitions.Notably,SmMn_(2)Ge_(2)displays significant magnetic anisotropy with easy magnetization direction switching from the c axis to the ab plane as temperature decreases.The critical behavior of the ferromagnetic transition occurring above room temperature is thoroughly examined.Reliable and self-consistent critical exponents,includingβ=0.292(2),γ=0.924(8),andδ=4.164(6),along with the Curie temperature T_c=347 K,are extracted through various methods,which provide evidence for the coexistence of multiple magnetic interactions in SmMn_(2)Ge_(2).Further analysis reveals that the magnetic interaction of SmMn_(2)Ge_(2)is a long-range type with the interaction distance decaying as J(r)~r^(-4.35).