Open AccessMagnetic properties of rare-earth zigzag chain systems RAgSe2 (R = Ho, Er, Tm, and Yb)
Author(s) -
S. Mizutami,
Yudai Ohmagari,
Takahiro Onimaru,
Yasuyuki Shimura,
R. Yamamoto,
Kazunori Umeo,
Toshiro Takabatake
Publication year - 2022
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2164/1/012025
Subject(s) - antiferromagnetism , condensed matter physics , zigzag , magnetic moment , paramagnetism , magnetic susceptibility , orthorhombic crystal system , ground state , curie–weiss law , ferromagnetism , physics , materials science , crystallography , curie temperature , chemistry , crystal structure , atomic physics , geometry , mathematics
In an antiferromagnetic zigzag chain, competition between the nearest and next-nearest neighbor interactions could give rise to magnetic frustration. Magnetic semiconductors R AgSe 2 ( R = Ho, Er, Tm, and Yb) crystallize in the ErAgSe 2 -type orthorhombic structure, where the R ions form a zigzag chain along the orthorhombic a-axis. The magnetic susceptibility data for all the samples follow the Curie-Weiss law between 40 and 300 K. The values of the effective magnetic moment μ β α are close to those expected for the free R 3 + ions. Negative values of the paramagnetic Curie temperature θ ρ indicate antiferromagnetic interactions. For R = Ho and Tm, the specific heat C(T) data exhibit no anomaly down to 0.4 K, which is ascribed to the nonmagnetic singlet ground states under the crystalline electric fields. On the other hand, for R = Er, C ( T ) shows peaks at T 1 = 1.3 K and T 2 = 0.9 K, indicating successive antiferromagnetic transitions. For R = Yb, C ( T ) shows a lambda-type anomaly at T m = 1.8 K. The magnetic entropy at T m is only 30% of R ln2 expected for the ground state doublet, suggesting magnetic fluctuations above T m .