Field-insensitive heavy fermion features and phase transition in the caged-structure quasi-skutterudite Sm3 Ru4 Ge13

Abstract

The robust field-insensitive heavy fermion features in Sm 3 Ru 4 Ge 13 and the magnetic phase transition at T N

Field-Independent Features in the Magnetization and Specific Heat of Sm3Co4Ge13

“…A schematic of the crystal structure of Sm 3 Co 4 Ge 13 in Pm3n space group is presented in Figure 1a. The powder x ray diffractograms (PXRD) obtained from pulverized annealed samples confirmed the formation of Sm 3 Co 4 Ge 13 in cubic Pm3n space group symmetry similar to the other 3:4:13 compounds [13]. Figure 1b shows the refined pattern in the cubic space group.…”

“…In the inset of (a), the temperature region below T ≈ 10 K is shown magnified to highlight the robust nature of the phase transition in applied magnetic field. Field-insensitiveness of specific heat was observed in our previous work on the Sm-based intermetallic, Sm 3 Ru 4 Ge 13 [13]. A field-insensitive nature of this kind can arise from the multipolar order of the magnetic moments, which are not perturbed by the applied magnetic fields.…”

“…The phase purity of the compound was probed using backscattered-electron imaging and X-ray microanalysis using a Cameca SX 100 electron microprobe (EPMA). The EPMA experiments were performed in a manner similar to that described in our previous work on a similar compound [13]. Magnetization measurements were performed in a Quantum Design Magnetic Property Measurement System (MPMS) and the specific heat measurements were performed in a Quantum Design Physical Property Measurement System (PPMS) together with a helium-3 cryogenic insert.…”

“…Field-insensitive features in the specific heat and other physical properties were recently observed in a 3:4:13 type intermetallic caged structure [13] which motivated us to investigate caged structures based on Samarium. Cobalt-based 3:4:13 quasi-skutterudites form a class of less-explored intermetallics despite displaying a very interesting suite of strongly correlated phenomena.…”

“…Intermetallics possessing caged structures around the rare earth show strongly correlated electron phenomena such as Kondo effect and field-insensitive specific heat suggesting octupolar order or valence fluctuation [12][13][14][15][16]. Sm-based caged compounds display field-insensitive specific heat which is attributed to multipole moments in the Γ 8 quartet crystalline electric field state.…”