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Infrared Properties of Electron Doped Cuprates: Tracking Normal State Gaps and Quantum Critical Behavior in Pr(2-x)Ce(x)CuO(4)

A. Zimmers·J. M. Tomczak·R. P. S. M. Lobo·N. Bontemps·C. P. Hill·M. C. Barr·Y. Dagan·R. L. Greene·A. J. Millis·C. C. Homes
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Abstract

We report the temperature dependence of the infrared-visible conductivity of Pr(2-x)Ce(x)CuO(4) thin films. When varying the doping from a non-superconducting film (x = 0.11) to a superconducting overdoped film (x = 0.17), we observe, up to optimal doping (x = 0.15), a partial gap opening. A model combining a spin density wave gap and a frequency and temperature dependent self energy reproduces our data reasonably well. The magnitude of this gap extrapolates to zero for x ~ 0.17 indicating the coexistence of magnetism and superconductivity in this material and the existence of a quantum critical point at this Ce concentration.

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A. Zimmers, J. M. Tomczak, R. P. S. M. Lobo, N. Bontemps, C. P. Hill, M. C. Barr, Y. Dagan, R. L. Greene, A. J. Millis, C. C. Homes. 2004-06-08. Infrared Properties of Electron Doped Cuprates: Tracking Normal State Gaps and Quantum Critical Behavior in Pr(2-x)Ce(x)CuO(4). https://doi.org/10.1209/epl%2Fi2004-10480-2

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