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arXiv · 1806.10766

Chemical- and hydrostatic-pressure effects on the Kitaev honeycomb material Na$_2$IrO$_3$

G. Simutis·N. Barbero·K. Rolfs·P. Leroy-Calatayud·K. Mehlawat·R. Khasanov·H. Luetkens·E. Pomjakushina·Y. Singh·H. -R. Ott·J. Mesot·A. Amato·T. Shiroka
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Abstract

The low-temperature magnetic properties of \tcr{polycrystalline} Na$_2$IrO$_3$, a candidate material for the realization of a quantum spin-liquid state, were investigated by means of muon-spin relaxation and nuclear magnetic resonance methods under chemical and hydrostatic pressure. The Li-for-Na chemical substitution promotes an inhomogeneous magnetic order, whereas hydrostatic pressure (up to 3.9\,GPa) results in an enhancement of the ordering temperature $T_\mathrm{N}$. In the first case, the inhomogeneous magnetic order suggests either short- or long-range correlations of broadly distributed $j=\,$\textonehalf\ Ir$^{4+}$ magnetic moments, reflecting local disorder. The increase of $T_\mathrm{N}$ under applied pressure points at an increased strength of three dimensional interactions arising from interlayer compression.

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G. Simutis, N. Barbero, K. Rolfs, P. Leroy-Calatayud, K. Mehlawat, R. Khasanov, H. Luetkens, E. Pomjakushina, Y. Singh, H. -R. Ott, J. Mesot, A. Amato, T. Shiroka. 2018-06-28. Chemical- and hydrostatic-pressure effects on the Kitaev honeycomb material Na$_2$IrO$_3$. https://doi.org/10.1103/physrevb.98.104421

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