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arXiv · 1606.07938

Spin liquid like Raman signatures in hyperkagome iridate Na$_4$Ir$_3$O$_8$

Satyendra Nath Gupta·P. V. Sriluckshmy·Ashiwini Balodhi·D. V. S. Muthu·S. R. Hassan·Yogesh Singh·T. V. Ramakrishnan·A. K. Sood
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Abstract

Combining Raman scattering measurements with mean field calculations of the Raman response we show that Kitaev-like magnetic exchange is dominant in the hyperkagome iridate Na$_4$Ir$_3$O$_8$. In the measurements we observe a broad Raman band at $\sim$~3500 cm$^{-1}$ with a band-width $\sim 1700$~cm$^{-1}$. Calculations of the Raman response of the Kitaev-Heisenberg model on the hyperkagome lattice shows that the experimental observations are consistent with calculated Raman response where Kitaev exchange interaction ($J_K$) is much larger than the Heisenberg term J$_1$ ($J_1/J_K \sim 0.1$). A comparison with the theoretical model gives an estimate of the Kitaev exchange interaction parameter.

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Satyendra Nath Gupta, P. V. Sriluckshmy, Ashiwini Balodhi, D. V. S. Muthu, S. R. Hassan, Yogesh Singh, T. V. Ramakrishnan, A. K. Sood. 2016-11-08. Spin liquid like Raman signatures in hyperkagome iridate Na$_4$Ir$_3$O$_8$. https://doi.org/10.1103/physrevb.94.155153

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