Resonance as a Measure of Pairing Correlations in the High-T_c superconductor YBa₂Cu₃O₆.₆

Author

Pengcheng Dai
Herbert A. Mook
Gabriel Aeppli
Stephen M. Hayden
Fatih Dogan, Missouri University of Science and TechnologyFollow

Abstract

One of the most striking properties of the high-transition-temperature (high-T_c) superconductors is that they are all derived from insulating antiferromagnetic parent compounds. The intimate relationship between magnetism and superconductivity in these copper oxide materials has intrigued researchers from the outset, because it does not exist in conventional superconductors. Evidence for this link comes from neutron-scattering experiments that show the unambiguous presence of short-range antiferromagnetic correlations (excitations) in the high-T_c superconductors. Even so, the role of such excitations in the pairing mechanism for superconductivity is still a subject of controversy. For YBa₂Cu₃O(6+x), where x controls the hole-doping level, the most prominent feature in the magnetic excitation spectrum is a sharp resonance (refs 6-11). Here we show that for underdoped YBa₂Cu₃O(6.6), where x and T_c are below their optimal values, modest magnetic fields suppress the resonance significantly, much more so for fields approximately perpendicular to the CuO₂ planes than for parallel fields. Our results indicate that the resonance measures pairing and phase coherence, suggesting that magnetism plays an important role in high-T_c superconductivity. The persistence of a field effect above T_c favours mechanisms in which the superconducting electron pairs are pre-formed in the normal state of underdoped copper oxide superconductors, awaiting transition to the superconducting state.

Recommended Citation

P. Dai et al., "Resonance as a Measure of Pairing Correlations in the High-T_c superconductor YBa₂Cu₃O₆.₆," Nature, vol. 406, no. 6799, pp. 965 - 968, Nature Publishing Group, Aug 2000.

The definitive version is available at https://doi.org/10.1038/35023094

Department(s)

Materials Science and Engineering

Keywords and Phrases

bilayer membrane; conductor; electric conductivity; magnetic field; magnetic stimulation; neutron scattering; probability

International Standard Serial Number (ISSN)

0028-0836

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2000 Nature Publishing Group, All rights reserved.

Publication Date

01 Aug 2000