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arXiv · 1612.08830

Investigation of Precursor Superconducting State in YBa$_2$Cu$_3$O$_{7-\delta}$ through In-plane Optical Spectroscopy

Kegan Lee·Keisuke Kamiya·Masamichi Nakajima·Shigeki Miyasaka·Setsuko Tajima
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Abstract

A precursor of superconductivity has been searched in the in-plane optical spectra of underdoped YBa$_2$Cu$_3$O$_y$, in which the previous $c$-axis optical spectra showed the presence of superconducting carriers at a temperature far above $T_c$ [Uykur $et al$., Phys. Rev. Lett. 112, 127003 (2014)][Dubroka $et al$., Phys. Rev. Lett. 106, 047006 (2011)]. By carefully subtracting the normal component from the imaginary part of conductivity $\sigma_2$($\omega$), we found a clear in-plane response of superconducting condensate at the temperature consistent with the $c$-axis optical data. This confirms that the precursory superconductivity developing with reducing a doping level is an intrinsic phenomenon in the cuprates.

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Kegan Lee, Keisuke Kamiya, Masamichi Nakajima, Shigeki Miyasaka, Setsuko Tajima. 2016-12-28. Investigation of Precursor Superconducting State in YBa$_2$Cu$_3$O$_{7-\delta}$ through In-plane Optical Spectroscopy. https://doi.org/10.7566/jpsj.86.023701

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