%0 Journal Article
%T Pressure-driven collapse of the relativistic electronic ground state in a honeycomb iridate
%J -
%D 2018
%R https://doi.org/10.1038/s41535-018-0109-0
%X Honeycomb-lattice quantum magnets with strong spin-orbit coupling are promising candidates for realizing a Kitaev quantum spin liquid. Although iridate materials such as Li2IrO3 and Na2IrO3 have been extensively investigated in this context, there is still considerable debate as to whether a localized relativistic wavefunction (Jeff£¿=£¿1/2) provides a suitable description for the electronic ground state of these materials. To address this question, we have studied the evolution of the structural and electronic properties of ¦Á-Li2IrO3 as a function of applied hydrostatic pressure using a combination of x-ray diffraction and x-ray spectroscopy techniques. We observe striking changes even under the application of only small hydrostatic pressure (P£¿¡Ü£¿0.1 GPa): a distortion of the Ir honeycomb lattice (via X-ray diffraction), a dramatic decrease in the strength of spin-orbit coupling effects (via X-ray absorption spectroscopy), and a significant increase in non-cubic crystal electric field splitting (via resonant inelastic X-ray scattering). Our data indicate that ¦Á-Li2IrO3 is best described by a Jeff£¿=£¿1/2 state at ambient pressure, but demonstrate that this state is extremely fragile and collapses under the influence of applied pressure
%U https://www.nature.com/articles/s41535-018-0109-0