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arXiv · 1007.4599

Interplay between quantum criticality and geometrical frustration in Fe3Mo3N with stella quadrangula lattice

Takeshi Waki·Shinsuke Terazawa·Teruo Yamazaki·Yoshikazu Tabta·Keisuke Sato·Akihiro Kondo·Koichi Kindo·Makoto Yokoyama·Yoshinori Takahashi·Hiroyuki Nakamura
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Abstract

In the eta-carbide-type correlated-electron metal Fe3Mo3N, ferromagnetism is abruptly induced from a nonmagnetic non-Fermi-liquid ground state either when a magnetic field (~14 T) applied to it or when it is doped with a slight amount of impurity (~5% Co). We observed a peak in the paramagnetic neutron scattering intensity at finite wave vectors, revealing the presence of the antiferromagnetic (AF) correlation hidden in the magnetic measurements. It causes a new type of geometrical frustration in the stellla quadrangula lattice of the Fe sublattice. We propose that the frustrated AF correlation suppresses the F correlation to its marginal point and is therfore responsible for the origin of the ferromagnetic (F) quantum critical behavior in pure Fe3Mo3N.

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Takeshi Waki, Shinsuke Terazawa, Teruo Yamazaki, Yoshikazu Tabta, Keisuke Sato, Akihiro Kondo, Koichi Kindo, Makoto Yokoyama, Yoshinori Takahashi, Hiroyuki Nakamura. 2010-07-27. Interplay between quantum criticality and geometrical frustration in Fe3Mo3N with stella quadrangula lattice. https://doi.org/10.1209/0295-5075%2F94%2F37004

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