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Commensurate spin dynamics in the superconducting state of an electron-doped cuprate superconductor

K. Yamada·K. Kurahashi·T. Uefuji·M. Fujita·S. Park·S. -H. Lee·Y. Endoh
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Abstract

We report neutron scattering studies on single crystals of the electron-doped (n-type) superconducting cuprate Nd2-xCexCuO4 (x=0.15) with Tc = 18 K and 25 K. Unlike the hole-doped (p-type) superconducting cuprates where incommensurate magnetic fluctuations commonly exist, the n-type cuprate shows commensurate magnetic fluctuations at the tetragonal (1/2 1/2 0) reciprocal points both in the superconducting and in the normal state. A spin gap opens up when the n-type cuprate becomes superconducting, as in the optimally doped p-type La2-xSrxCuO4. The gap energy, however, increases gradually up to about 4 meV as T decreases from Tc to 2 K, which contrasts with the spin pseudogap behavior with a T-independent gap energy in the superconducting state of p-type cuprates.

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K. Yamada, K. Kurahashi, T. Uefuji, M. Fujita, S. Park, S. -H. Lee, Y. Endoh. 2002-10-24. Commensurate spin dynamics in the superconducting state of an electron-doped cuprate superconductor. https://doi.org/10.1103/physrevlett.90.137004

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