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arXiv · 1008.2022

The magnetic structure of the $zigzag$ chain family Na$_{x}$Ca$_{1-x}$V$_2$O$_4$ determined by muon-spin rotation

Oren Ofer·Yutaka Ikedo·Tatsuo Goko·Martin Mansson·Jun Sugiyama·Eduardo J. Ansaldo·Jess H. Brewer·Kim H. Chow·Hiroya Sakurai
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Abstract

We present muon-spin rotation measurements on polycrystalline samples of the complete family of the antiferromagnetic (AF) $zigzag$ chain compounds, Na$_x$Ca$_{1-x}$V$_2$O$_4$. In this family, we explore the magnetic properties from the metallic NaV$_2$O$_4$ to the insulating CaV$_2$O$_4$. We find a critical $x_c(\sim0.833)$ which separates the low and high Na-concentration dependent transition temperature and its magnetic ground state. In the $x x_c$ compounds, multiple sub-phases appear with temperature and $x$. Based on the muon data obtained in zero external magnetic field, a careful dipolar field simulation was able to reproduce the muon behavior and indicates a modulated helical incommensurate spin structure of the metallic AF phase. The incommensurate modulation period obtained by the simulation agrees with that determined by neutron diffraction.

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Oren Ofer, Yutaka Ikedo, Tatsuo Goko, Martin Mansson, Jun Sugiyama, Eduardo J. Ansaldo, Jess H. Brewer, Kim H. Chow, Hiroya Sakurai. 2010-08-11. The magnetic structure of the $zigzag$ chain family Na$_{x}$Ca$_{1-x}$V$_2$O$_4$ determined by muon-spin rotation. https://doi.org/10.1103/physrevb.82.094410

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