Nature 442, 59-62 (6 July 2006) | doi:10.1038/nature04857; Received 9 February 2006; Accepted 27 April 2006

Resonance in the electron-doped high-transition-temperature superconductor Pr0.88LaCe0.12CuO4-delta

Stephen D. Wilson1, Pengcheng Dai1,2, Shiliang Li1, Songxue Chi1, H. J. Kang3,4 & J. W. Lynn3

  1. Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996-1200, USA
  2. Center for Neutron Scattering, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
  3. NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8562, USA
  4. Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, USA

Correspondence to: Pengcheng Dai1,2 Correspondence and requests for materials should be addressed to P.D. (Email: daip@ornl.gov).

In conventional superconductors, the interaction that pairs the electrons to form the superconducting state is mediated by lattice vibrations1 (phonons). In high-transition-temperature (high-T c) copper oxides, it is generally believed that magnetic excitations might play a fundamental role in the superconducting mechanism because superconductivity occurs when mobile 'electrons' or 'holes' are doped into the antiferromagnetic parent compounds2. Indeed, a sharp magnetic excitation termed 'resonance' has been observed by neutron scattering in a number of hole-doped materials3, 4, 5, 6, 7, 8, 9, 10, 11. The resonance is intimately related to superconductivity12, and its interaction with charged quasi-particles observed by photoemission13, 14, optical conductivity15, and tunnelling16 suggests that it might play a part similar to that of phonons in conventional superconductors. The relevance of the resonance to high-T c superconductivity, however, has been in doubt because so far it has been found only in hole-doped materials17. Here we report the discovery of the resonance in electron-doped superconducting Pr0.88LaCe0.12CuO4-delta (T c = 24 K). We find that the resonance energy (E r) is proportional to T c via E r approximately 5.8k B T c for all high-T c superconductors irrespective of electron- or hole-doping. Our results demonstrate that the resonance is a fundamental property of the superconducting copper oxides and therefore must be essential in the mechanism of superconductivity.


These links to content published by NPG are automatically generated.


Spins in superconductors Mobile or not?

Nature Physics News and Views (01 Sep 2009)

Superconductivity Copper oxides get charged up

Nature News and Views (22 Nov 2001)