The Connection Between Superconducting Phase Correlations and Spin Excitations in YBa2Cu3O6.6: A Magnetic Field Study
Abstract
One of the most striking universal properties of the high-transition-temperature (high-Tc) superconductors is that they are all derived from the hole-doping of their insulating antiferromagnetic (AF) parent compounds. From the outset, the intimate relationship between magnetism and superconductivity in these copper-oxides has intrigued researchers. Evidence for this link comes from neutron scattering experiments that show the unambiguous presence of short-range AF correlations (excitations) in cuprate superconductors. Even so, the role of such excitations in the pairing mechanism and superconductivity is still a subject of controversy. For YBa2Cu3O6.6, where x controls the hole-doping level, the most prominent feature in the magnetic excitations spectra is the ``resonance''. Here we show that for underdoped YBa2Cu3O6.6, where x and Tc are below the optimal values, modest magnetic fields suppress the resonance significantly, much more so for fields approximately perpendicular rather than parallel to the CuO2 planes. Our results indicate that the resonance measures pairing and phase coherence, suggesting that magnetism plays an important role in the superconductivity of cuprates. The persistence of a field effect above Tc favors mechanisms with preformed pairs in the normal state of underdoped cuprates.
Recommended Citation
P. Dai et al., "The Connection Between Superconducting Phase Correlations and Spin Excitations in YBa2Cu3O6.6: A Magnetic Field Study," arXiv preprint cond-mat/0006433, Cornell University, Jun 2000.
The definitive version is available at https://doi.org/10.48550/arXiv.cond-mat/0006433
Department(s)
Materials Science and Engineering
Document Type
Article - Journal
Document Version
Preprint
File Type
text
Language(s)
English
Publication Date
2000-06-28
