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arXiv · 1701.03472

Unconventional magnetic phase separation in $\gamma$-CoV$_2$O$_6$

L. Shen·M. Laver·E. M. Forgan·E. Jellyman·E. Canévet·J. Schefer·Z. He·M. Itoh·E. Blackburn
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Abstract

We have explored the magnetism in the non-geometrically frustrated spin-chain system $\gamma$-CoV$_{2}$O$_{6}$ which possesses a complex magnetic exchange network. Our neutron diffraction patterns at low temperatures ($T$ $\leqslant$ $T_{\mathrm{N}}$ = 6.6 K) are best described by a model in which two magnetic phases coexist in a volume ratio 65(1) : 35(1), with each phase consisting of a single spin modulation. This model fits previous studies and our observations better than the model proposed by Lenertz $et$ $al$ in J. Phys. Chem. C 118, 13981 (2014), which consisted of one phase with two spin modulations. By decreasing the temperature from $T_{\mathrm{N}}$, the minority phase of our model undergoes an incommensurate-commensurate lock-in transition at $T^{*}$ = 5.6 K. Based on these results, we propose that phase separation is an alternative approach for degeneracy-lifting in frustrated magnets.

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L. Shen, M. Laver, E. M. Forgan, E. Jellyman, E. Canévet, J. Schefer, Z. He, M. Itoh, E. Blackburn. 2017-01-12. Unconventional magnetic phase separation in $\gamma$-CoV$_2$O$_6$. https://doi.org/10.1103/physrevb.96.054420

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