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arXiv · 1801.09342

Observation of tunneling gap in epitaxial ultrathin films of pyrite-type copper disulfide

Chong Liu·Haohao Yang·Can-Li Song·Wei Li·Ke He·Xu-Cun Ma·Lili Wang·Qi-Kun Xue
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Abstract

We report scanning tunneling microscopy investigation on epitaxial ultrathin films of pyrite-type copper disulfide. Layer by layer growth of CuS2 films with a preferential orientation of (111) on SrTiO3(001) and Bi2Sr2CaCu2O8+δ substrates is achieved by molecular beam epitaxy growth. For ultrathin films on both kinds of substrates, we observed symmetric tunneling gap around Fermi level that persists up to ~ 15 K. The tunneling gap degrades with either increasing temperature or increasing thickness, suggesting new matter states at the extreme two dimensional limit.

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Chong Liu, Haohao Yang, Can-Li Song, Wei Li, Ke He, Xu-Cun Ma, Lili Wang, Qi-Kun Xue. 2018-01-29. Observation of tunneling gap in epitaxial ultrathin films of pyrite-type copper disulfide. https://doi.org/10.1088/0256-307x%2F35%2F2%2F027303

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