Anomalous normal-state resistivity in superconducting La2−xCexCuO4: Fermi liquid or strange metal?

Abstract

We present experimental results for the in-plane resistivity of the electron-doped cuprate superconductor La2−xCexCuO4 above its transition temperature Tc as a function of Ce doping x and temperature. For the doping x between 0.11 and 0.17, where Tc varies from 30 K (x=0.11) to 5 K (x=0.17), we find that the resistivity shows a T2 behavior for all values of doping over the measurement range from 70 to 250 K. The coefficient of the T2 resistivity term decreases with increasing x following the trend in Tc. We analyze our data theoretically and posit that n-type cuprates are better thought of as strange metals. Although the quadratic temperature dependence appears to be in naive agreement with the Fermi-liquid (FL) expectations, the facts that the measured resistivity is large and approximate T2 scattering dominates the resistivity even up to 400 K argue against a standard normal-metal FL picture being applicable. We discuss possible origins of the strange-metal behavior.

Source-reported materials — not catalogue approval

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