Distinct order of Gd4fand Fe3dmoments coexisting inGdFe

Abstract

Single crystals of flux-grown tetragonal GdFe4Al8 were characterized by thermodynamic, transport, and x-ray resonant magnetic scattering measurements. In addition to antiferromagnetic order at TN ≈ 155 K, two low-temperature transitions at T1 ≈ 21 K and T2 ≈ 27 K were identified. The Fe moments order at TN with an incommensurate propagation vector (τ, τ, 0) with τ varying between 0.06 and 0.14 as a function of temperature, and maintain this order over the entire T < TN range. The Gd 4f moments order below T2 with a ferromagnetic component mainly out of plane. Below T1, the ferromagnetic components are confined to the crystallographic plane. Remarkably, at low temperatures the Fe moments maintain the same modulation as at high temperatures, but the Gd 4f moments apparently do not follow this modulation. The magnetic phase diagrams for fields applied in [110] and [001] direction are presented and possible magnetic structures are discussed.

Crystal structure and properties of tetragonal EuAg4In8 grown by metal flux technique

“…In continuation to our studies in the RET 4 X 8 family and related compounds in this series, we found that EuAg 4 In 8 exists in tetragonal phase as well. The other motivation of this work is that the compounds having general formula RET 4 X 8 (RE¼La-Nd, Sm-Lu and U; T¼Cr, Mn, Fe, Cu and Ag; X¼ Al, Ga and In) are generally well known for their interesting physical properties like high temperature antiferromagnetic ordering (T N ) in GdFe 4 Al 8 [30] (T N ¼155 K) along with two low temperature transitions at T 1 ¼ 21 K and T 2 ¼27 K, high temperature magnetic ordering (163.5 K) in TbFe 4 Al 8 [31], anisotropic magnetic properties of single crystals of UFe 4 Al 8 [32] and the antiferromagnetic-paramagnetic transitions at T N ¼6.50 and 6.75 K in GdCr x Al 12À x (x¼ 3.5 and 4.0) [33].…”

New Structure Type in the Mixed-Valent Compound YbCu4Ga8

“…Compounds having general formula RET 4 X 8 (RE = La–Nd, Sm–Lu, and U; T = Cr, Mn, Fe, Co, Cu, and Ag; X = Al, Ga, and In) have been reported for their interesting physical properties. − For example, high-temperature antiferromagnetic ordering ( T N ) observed in GdFe 4 Al 8 ( T N = 155 K) in addition to the two low-temperature magnetic transitions at T 1 = 21 K and T 2 = 27 K, high-temperature magnetic ordering (163.5 K) in TbFe 4 Al 8 , anisotropic magnetic properties on the single crystals of UFe 4 Al 8 , and some more compounds are reported in the REFe 4 Al 8 family. − The antiferromagnetic–paramagnetic transitions are observed in GdCr x Al 12– x at T N = 6.50 and 6.75 K for x = 3.5 and 4.0, respectively …”