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Magnetic penetration depth in electron-doped cuprates - evidence for gap nodes

R. Prozorov·R. W. Giannetta·P. Fournier·R. L. Greene
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Abstract

The in-plane penetration depth λ(T) is measured in electron-doped single crystals Nd1.85Ce0.15CuO4-x (NCCO) and Pr1.85Ce0.15CuO4-x (PCCO) using a 11 MHz LC resonator. In NCCO, λ(T) exhibits a minimum at 3.8 K and a pronounced upturn down to 0.4 K due to the paramagnetic contribution of Nd3+ ions. The London penetration depth contribution is linear in T. The paramagnetic contribution is absent in PCCO, where λ(T)~T^2 at low temperatures. Our results indicate the presence of nodes in the superconducting gap, i.e., non s-wave symmetry of the order parameter in electron-doped cuprates.

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R. Prozorov, R. W. Giannetta, P. Fournier, R. L. Greene. 1999-12-01. Magnetic penetration depth in electron-doped cuprates - evidence for gap nodes. https://doi.org/10.1016/s0921-4534(00)00945-x

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