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arXiv · 1301.2970

ω/T scaling of the optical conductivity in strongly correlated layered cobalt oxide

P. Limelette·V. Ta Phuoc·F. Gervais·R. Fresard
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Abstract

We report infrared spectroscopic properties of the strongly correlated layered cobalt oxide [BiBa$_{0.66}$K$_{0.36}$O$_2$]CoO$_2$. These measurements performed on single crystals allow us to determine the optical conductivity as a function of temperature. In addition to a large temperature dependent transfer of spectral weight, an unconventional low energy mode is found. We show that both its frequency and damping scale as the temperature itself. In fact, a basic analysis demonstrates that this mode fully scales onto a function of $ω$/T up to room temperature. This behavior suggests low energy excitations of non-Fermi liquid type originating from quantum criticality.

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P. Limelette, V. Ta Phuoc, F. Gervais, R. Fresard. 2013-01-14. ω/T scaling of the optical conductivity in strongly correlated layered cobalt oxide. https://doi.org/10.1103/physrevb.87.035102

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