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arXiv · 1008.5230

Visualizing topological insulating Bi2Te3 quintuple layers on SiO2-capped Si substrates and its contrast optimization

Zhaoguo Li·Yuyuan Qin·Yuewen Mu·Taishi Chen·Changhui Xu·Longbing He·Wangfeng Ding·Jianguo Wan·Fengqi Song·Min Han·Guanghou Wang
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Abstract

Thin Bi2Te3 flakes, with as few as 3 quintuple layers, are optically visualized on the SiO2-capped Si substrates. Their optical contrasts vary with the illumination wavelength, flake thickness and capping layers. The maximum contrast appears at the optimized light with the 570nm wavelength. The contrast turns reversed when the flake is reduced to less than 20 quintuple layers. A calculation based on the Fresnel law describes the above observation with the constructions of the layer number-wave length-contrast three-dimensional (3D) diagram and the cap thickness-wavelength-contrast 3D diagram, applicative in the current studies of topological insulating flakes.

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Zhaoguo Li, Yuyuan Qin, Yuewen Mu, Taishi Chen, Changhui Xu, Longbing He, Wangfeng Ding, Jianguo Wan, Fengqi Song, Min Han, Guanghou Wang. 2010-12-15. Visualizing topological insulating Bi2Te3 quintuple layers on SiO2-capped Si substrates and its contrast optimization. https://arxiv.org/abs/1008.5230

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