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arXiv · 2408.03080

Correlation between $T_{\mathrm{c}}$ and the Pseudogap Observed in the Optical Spectra of High $T_{\mathrm{c}}$ Superconducting Cuprates

Setsuko Tajima·Yuhta Itoh·Katsuya Mizutamari·Shigeki Miyasaka·Masamichi Nakajima·Nae Sasaki·Shunpei Yamaguchi·Kei-ichi Harada·Takao Watanabe
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Abstract

We studied the temperature dependences of the optical spectra for optimally and underdoped Bi$_2$Sr$_2$Ca$_2$Cu$_3$O$_{10+z}$ single crystals. Similarly to the other cuprates' cases, a gap-like conductivity suppression was observed with reducing the temperature from above $T_{\mathrm{c}}$, creating a peak in the conductivity spectrum. The conductivity peak energy was insensitive to the doping level, namely $T_{\mathrm{c}}$, which suggests that this gap is not a superconducting gap but is related to the pseudogap. Comparing the data of various mono-, double-, and triple-layer cuprates, we found a clear correlation between the optimal $T_{\mathrm{c}}$ of each material and the pseudogap-related conductivity peak energy.

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Setsuko Tajima, Yuhta Itoh, Katsuya Mizutamari, Shigeki Miyasaka, Masamichi Nakajima, Nae Sasaki, Shunpei Yamaguchi, Kei-ichi Harada, Takao Watanabe. 2024-08-06. Correlation between $T_{\mathrm{c}}$ and the Pseudogap Observed in the Optical Spectra of High $T_{\mathrm{c}}$ Superconducting Cuprates. https://doi.org/10.7566/jpsj.93.103701

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