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arXiv · 1911.12920

Reflection anisotropy experiments to study non-equilibrium dynamics of electronic nematicity

Inho Kwak·Jaeseok Son·Bumjoo Lee·Thomas Wolf·Changhee Sohn·Tae Won Noh·K. W. Kim
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Abstract

Electronic nematicity have attracted a great deal of interest in the unconventional superconductivity research. We present an experimental method to investigate reflectivity anisotropy by the electronic nematicity and its non-equilibrium dynamics. Our experimental results on Ba(Fe$_{0.955}$Co$_{0.045}$)$_{2}$As$_{2}$ single crystal clearly feature the broken four-fold symmetry along directions parallel to Fe-Fe bonding. Numerical simulations using WVASE from Woollam Co. demonstrate that our method is highly reliable under various experimental conditions. Finally, we perform time-resolved reflectivity anisotropy measurement confirming that photo-excitation by 1.55 eV photons suppresses the reflectivity anisotropy due to nematic order.

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Inho Kwak, Jaeseok Son, Bumjoo Lee, Thomas Wolf, Changhee Sohn, Tae Won Noh, K. W. Kim. 2019-11-29. Reflection anisotropy experiments to study non-equilibrium dynamics of electronic nematicity. https://arxiv.org/abs/1911.12920

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