Minimal model for the magnetic phase diagram of CeTi 1−x Sc x Ge, GdFe 1−x Cox Si, and related materials,

JULIAN G. SERENI; SERGIO ENCINA; P.PEDRAZZINI; VICTOR CORREA

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2020 vol. 503 p. 166614 - 166614

0304-8853

The local nature of the highest antiferromagnetic (AFM) temperature in Ce based compounds wasreported for CeScGe with TN = 47 K and this character extends all along the CeSc1-yTiyGe alloyswithin the range of stability of the CeScSi-type structure: 0 ≤ y ≤ 0.75. Along this concentrationrange a complex magnetic phase diagram with a continuous modification of its anisotropic magnetic behavior is observed: AFM between 0 ≤ y ≤ 0.4 (with 47 K≥ TN ≥ 19 K) and ferromagnetic(FM) for 0.50 ≤ y ≤ 0.75 (with 16 K≥ TC ≥ 7 K). The stability of each magnetic phase is howeverquestioned because a second AFM transition occurs at TL(y), slightly below TN(y). Both transitionconverge at a critical region (0.4 ≤ ycr ≤ 0.6) where the FM behavior takes over. These thermaland concentration magnetic instabilities are re-investigated performing more detailed magnetic andtransport measurements that confirming the competition between different magnetic structures ofsimilar energy. Respective preeminence depend on two main parameters: the electronic concentration driven by the Sc/Ti substitution and on the thermal occupation of the ground and excited CEFstates.