Open AccessAnisotropic magnetic coupling with a two-dimensional characteristic in noncentrosymmetric Cr11Ge19
Author(s) -
Hui Han,
Lei Zhang,
Xiangde Zhu,
Haifeng Du,
Gao Min,
Langsheng Ling,
Li Pi,
Changjin Zhang,
Yuheng Zhang
Publication year - 2016
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep39338
Subject(s) - condensed matter physics , critical exponent , magnetic anisotropy , magnetism , anisotropy , magnetization , ferromagnetism , ground state , magnetic moment , coupling (piping) , exponent , physics , magnetic field , materials science , phase transition , atomic physics , quantum mechanics , linguistics , philosophy , metallurgy
In this work, we successfully synthesize the single crystal Cr 11 Ge 19 . The magnetism of the noncentrosymmetric Cr 11 Ge 19 with itinerant ferromagnetic ground state is thoroughly investigated on the single crystal. Based on the variation measurements including the angular rotation, temperature, and magnetic field dependence of magnetization, we find that this material exhibits strong magnetic anisotropy along the c -axis. To clearly reveal the magnetic interactions, the critical behavior is studied using the modified Arrott plot, the Kouvel-Fisher method, and the critical isotherm technique. Combining these different methods, three main critical exponents ( β, γ , and δ ) are obtained. The critical exponent β is close to the theoretical prediction of a three-dimensional XY model with spin-dimensionality n = 2, indicating two-dimensional magnetic coupling. Meanwhile, the critical exponent γ suggests that the magnetic interaction is of long-range type with magnetic exchange distance decaying as J( r ) ≈ r −4.61 . We propose that the ferromagnetic ground state of Cr 11 Ge 19 is formed by the polarized magnetic moments along the c -axis, while the long-range magnetic coupling is established within the ab plane.