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Infrared Hall conductivity of Na$_{0.7}$CoO$_2$

E. J. Choi·S. H. Jung·J. H. Noh·A. Zimmers·D. Schmadel·H. D. Drew·J. Y. Son·J. H. Cho
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Abstract

We report infrared Hall conductivity $σ_{xy}(ω)$ of Na$_{0.7}$CoO$_2$ thin films determined from Faraday rotation angle $θ_{F}$ measurements. $σ_{xy}(ω)$ exhibits two types of hole conduction, Drude and incoherent carriers. The coherent Drude carrier shows a large renormalized mass and Fermi liquid-like behavior of Hall scattering rate, $γ_{H} \sim aT^{2}$. The spectral weight is suppressed and disappears at T = 120K. The incoherent carrier response is centered at mid-IR frequency and shifts to lower energy with increasing T. Infrared Hall constant is positive and almost independent of temperature in sharp contrast with the dc-Hall constant.

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E. J. Choi, S. H. Jung, J. H. Noh, A. Zimmers, D. Schmadel, H. D. Drew, J. Y. Son, J. H. Cho. 2006-11-03. Infrared Hall conductivity of Na$_{0.7}$CoO$_2$. https://doi.org/10.1103/physrevb.76.033105

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