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arXiv · 2103.04295

Robust noncoplanar magnetism in band filling-tuned (Nd$_{1-x}$Ca$_x$)$_2$Mo$_2$O$_7$

Max Hirschberger·Yoshio Kaneko·Leonie Spitz·Taro Nakajima·Yasujiro Taguchi·Yoshinori Tokura
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Abstract

In the metallic pyrochlore Nd$_2$Mo$_2$O$_7$, the conducting Molybdenum sublattice adopts canted, yet nearly collinear ferromagnetic order with nonzero scalar spin chirality. The chemical potential may be controlled by replacing Nd$^{3+}$ with Ca$^{2+}$, while introducing only minimal additional disorder to the conducting states. Here, we demonstrate the stability of the canted ferromagnetic state, including the tilting angle of Molybdenum spins, in (Nd$_{1-x}$Ca$_{x}$)$_2$Mo$_2$O$_7$ (NCMO) with $x\le 0.15$ using magnetic susceptibility measurements. Mo-Mo and Mo-Nd magnetic couplings both change sign above $x=0.22$, where the canted ferromagnetic state gives way to a spin-glass metallic region. Contributions to the Curie-Weiss law from two magnetic sublattices are separated systematically.

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Max Hirschberger, Yoshio Kaneko, Leonie Spitz, Taro Nakajima, Yasujiro Taguchi, Yoshinori Tokura. 2021-03-07. Robust noncoplanar magnetism in band filling-tuned (Nd$_{1-x}$Ca$_x$)$_2$Mo$_2$O$_7$. https://doi.org/10.1103/physrevb.104.024436

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