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Anisotropic Optical Conductivity of Nd2-xCexCuO4 Thin Films

Takashi Yanagisawa·Shigeru Koikegami·Hajime Shibata·Shinji Kimura·Satoshi Kashiwaya·Akihito Sawa·Noritaka Matsubara·Koki Takita
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Abstract

Opticcal conductivity spectra $σ_1(ω)$ of Nd2-xCexCuO4 thin films, measured by the reflectance-transmittance method (R-T method) which has been proposed to investigate far-infrared spectroscopy, are investigated based on the anisotropic pairing model. Precise measurements of the frequency-dependent conductivity enable us to examine quantitatively the nature of the superconducting gap through infrared properties in the electron-doped high-Tc superconductors. We show that the behavior of optical conductivity $σ_1$ is consistent with the anisotropic superconducting gap and is well explained by the formula for d-wave pairing in the low-energy regime of the far-infrared region. Our results suggest that the electron-doped cuprate superconductors Nd2-xCexCuO4 have nodes in the superconducting gap.

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Takashi Yanagisawa, Shigeru Koikegami, Hajime Shibata, Shinji Kimura, Satoshi Kashiwaya, Akihito Sawa, Noritaka Matsubara, Koki Takita. 2002-04-15. Anisotropic Optical Conductivity of Nd2-xCexCuO4 Thin Films. https://doi.org/10.1143/jpsj.70.2833

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