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arXiv · 1109.1479

Observation of the predicted charge collective mode of the Tc = 45 K superconducting phase of La2CuO4+δ

Y. H. Kim·Y. S. Song·P. H. Hor
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Abstract

We report the far-infrared (far-IR) observation of the Goldstone mode at ~ 72 cm-1 (~ 9 meV) predicted to exist in the superconducting phase of the transition temperature (Tc) at 45 K in the La2CuO4-based superconductors. Our observation furthers the experimental support for the two-component picture where the localized charge texture, formed at a specific planar hole density (Ppl), is tied to the HTS at Tc = 15 K, 30 K, and 45 K in a hierarchical fashion at the so-called "magic" doping level at Ppl = 1/16, 2/16, and 3/16 respectively.

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Y. H. Kim, Y. S. Song, P. H. Hor. 2011-09-07. Observation of the predicted charge collective mode of the Tc = 45 K superconducting phase of La2CuO4+δ. https://doi.org/10.1142/s0217984911500205

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