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arXiv · 1407.3539

Observation of pseudogap-like feature above Tc in LiFeAs and (Ba0.6K0.4)Fe2As2 by ultrafast optical measurement

Kung-Hsuan Lin·Kuan-Jen Wang·Chung-Chieh Chang·Yu-Chieh Wen·Dzung-Han Tsai·Yu-Ruei Wu·Yao-Tsung Hsieh·Ming-Jye Wang·Bing Lv·Paul Ching-Wu Chu·Maw-Kuen Wu
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Abstract

We utilize ultrafast optical measurement to study the quasiparticle relaxation in stoichiometric LiFeAs and nearly optimally doped (BaK)Fe2As2 crystals. According to our temperature-dependent studies of LiFeAs, we have observed pseudogap-like feature at onset temperature of ~ 55 K, which is above Tc = 15 K. In addition, the onset temperature of pseudogap ~90K was also observed in Ba0.6K0.4Fe2As2 (Tc = 36 K). Our findings seem implying that the pseudogap feature, which is due to antiferromagnetic fluctuations, is universal for the largely studied 11, 111, 122, and 1111 iron-based superconductors.

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Kung-Hsuan Lin, Kuan-Jen Wang, Chung-Chieh Chang, Yu-Chieh Wen, Dzung-Han Tsai, Yu-Ruei Wu, Yao-Tsung Hsieh, Ming-Jye Wang, Bing Lv, Paul Ching-Wu Chu, Maw-Kuen Wu. 2014-07-14. Observation of pseudogap-like feature above Tc in LiFeAs and (Ba0.6K0.4)Fe2As2 by ultrafast optical measurement. https://arxiv.org/abs/1407.3539

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