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arXiv · 2303.16745

Pressure tuning of optical reflectivity in LuH2

Xuan Zhao·Pengfei Shan·Ningning Wang·Yunliang Li·Yang Xu·Jinguang Cheng
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Abstract

Recently, the claim of room-temperature superconductivity in nitrogen-doped lutetium hydride at near-ambient conditions has attracted tremendous attention. Criticism of the work rises shortly, while further explorations are needed to settle the dispute. One of the intriguing observations is the pressured-induced color change, which has been reproduced in the lutetium dihydride LuH2 while its mechanism remains unclear. Through optical reflectivity measurements of LuH2 in the visible to near-infrared region, we observe strong light absorption next to the sharp plasmon resonance, which continuously shifts to higher energies with increasing pressure. It gives rise to the increased reflection of red light and suppressed reflection of blue light. Our work sheds light on resolving the puzzles regarding the pressure induced color change in LuH2.

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Xuan Zhao, Pengfei Shan, Ningning Wang, Yunliang Li, Yang Xu, Jinguang Cheng. 2023-03-29. Pressure tuning of optical reflectivity in LuH2. https://doi.org/10.1016/j.scib.2023.04.009

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