First-order phase transition to strongly anisotropic ferromagnetism in Tl2Fe6Te6

Large low field magnetocaloric effect in first-order phase transition compound TlFe3Te3 with low-level hysteresis

“…All the diffraction peaks could be indexed by a hexagonal structure with space group P6 3 /m. The lattice parameters a  = 9.355(1) Å and c  = 4.224(5) Å were obtained by the refinement, which are in good agreement with previous reports44. The electron probe micro-analyzer (EPMA) experiments performed on several single crystals verified that the sample composition (the average atomic ratio) is of Tl : Fe : Te = 0.99(1) : 2.95(2) : 3.00(1), which is in consistent with the nominal composition.…”

“…As shown in Fig. 2(c,d), it is clear that the M ( T ) curves near T C exhibit a small thermal hysteresis for both directions, which is in contrast to that reported by Uhl et al 43 and Pelizzone et al 44, who did not observe any hysteresis in their measurements. We observed a distinguishable but very small hysteresis, ( i.e.…”

“…Larger magnetization along c -axis suggests that the easy axis of magnetization is in the c axis. As discussed by Uhl et al 43 and Pelizzone et al 44, the strong magnetic anisotropy observed in the ferromagnetic state is certainly related to its peculiar structure being composed of |Fe 3 Te 3 | ∞ chains, whose central part is a column of edge-sharing octahedral Fe clusters. The Fe-Fe distance of 2.6 Å within the clusters are comparable to the interatomic distance in metallic iron, while the nearest two Fe atoms belong to different |Fe 3 Te 3 | ∞ chains are 6.7 Å apart.…”

“…The crystal structure and physical properties of TlFe 3 Te 3 were reported by two groups in 19844344. TlFe 3 Te 3 crystalizes in a hexagonal structure with space group P6 3 /m, which consists of one-dimensional metallic cluster |Fe 3 Te 3 | ∞ chains along the hexagonal c -axis, separated by the parallel chains of Tl atoms (see Fig.…”