Ultrasonic Study on the Hexagonal Antiferromagnet Dy3Ru4Al12

International Conference on Strongly Correlated Electron Systems 2016

Ishii, I.^1 ; Takezawa, K.^1 ; Goto, H.^1 ; Kamikawa, S.^1 ; Andreev, A.V.^2 ; Gorbunov, D.I.^2,3 ; Henriques, M.S.^2 ; Suzuki, T.^1,4,5

Department of Quantum Matter, ADSM, Hiroshima University, Higashi-Hiroshima

739-8530, Japan^1

Institute of Physics, Academy of Sciences, Na Slovance 2, Prague

182 21, Czech Republic^2

Dresden High Magnetic Field Laboratory, Helmholtz-Zentrum Dresden-Rossendorf, Dresden

D-01314, Germany^3

Institute for Advanced Materials Research, Hiroshima University, Higashi-Hiroshima

739-8530, Japan^4

Cryogenics and Instrumental Analysis Division, N-BARD, Hiroshima University, Higashi-Hiroshima

739-8526, Japan^5

关键词: Crystal electric field;    Elastic softening;    High temperature;    Longitudinal elastic modulus;    Quadrupole coupling constants;    Single-crystalline;    Transverse modulus;    Ultrasonic study;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/807/1/012002/pdf
DOI  :  10.1088/1742-6596/807/1/012002

来源: IOP

【 摘 要 】

In the distorted kagome lattice antiferromagnet Dy3Ru4Al12with TN= 7 K, a crystal electric field (CEF) effect is expected at high temperatures. To investigate the CEF effect and the phase transition at TN, we performed ultrasonic measurements on a single-crystalline sample. At high temperatures, both the longitudinal elastic modulus C11and the transverse modulus C44increase monotonically with decreasing temperature. Below 60 K a characteristic elastic softening is observed in C44in contrast to C11with monotonic hardening down to TN. We analyzed C44using the Curie-Weiss-type equation and obtained a negative parameter: Θ which is proportional to a quadrupole-quadrupole coupling constant under the hexagonal CEF. With further decreasing temperature, both moduli exhibit abrupt elastic hardening at TNdue to a magnetostriction.