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arXiv · 0807.1861

Electronic liquid crystal state in the high-temperature superconductor YBCO(6.45)

V. Hinkov·D. Haug·B. Fauque·P. Bourges·Y. Sidis·A. Ivanov·C. Bernhard·C. T. Lin·B. Keimer
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Abstract

Electronic phases with symmetry properties matching those of conventional liquid crystals have recently been discovered in transport experiments on semiconductor heterostructures and metal oxides at milli-Kelvin temperatures. We report the spontaneous onset of a onedimensional, incommensurate modulation of the spin system in the high-temperature superconductor YBa2Cu3O6.45 upon cooling below ~150 K, while static magnetic order is absent above 2 K. The evolution of this modulation with temperature and doping parallels that of the in-plane anisotropy of the resistivity, indicating an electronic nematic phase that is stable over a wide temperature range. The results suggest that soft spin fluctuations are a microscopic route towards electronic liquid crystals, and nematic order can coexist with high-temperature superconductivity in underdoped cuprates.

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V. Hinkov, D. Haug, B. Fauque, P. Bourges, Y. Sidis, A. Ivanov, C. Bernhard, C. T. Lin, B. Keimer. 2008-07-11. Electronic liquid crystal state in the high-temperature superconductor YBCO(6.45). https://doi.org/10.1126/science.1152309

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