Evidence for two electronic components in high-temperature superconductivity from NMR
J Haase1, C P Slichter, G V M Williams
1Faculty of Physics and Earth Science, University of Leipzig, D-04103 Leipzig, Germany.
Summary
This study analyzes nuclear magnetic resonance (NMR) data for lanthanum strontium cuprate, suggesting a two-component system. This finding challenges the prevailing one-component model for cuprates.
Area of Science:
- Condensed matter physics
- Materials science
- Solid-state chemistry
Background:
- Cuprates, such as lanthanum strontium cuprate (La(1.85)Sr(0.15)CuO(4)), are complex materials with unique electronic properties.
- The prevailing model describes cuprates as a one-component system, but some evidence suggests a more complex behavior.
Purpose of the Study:
- To re-examine nuclear magnetic resonance (NMR) shift data for La(1.85)Sr(0.15)CuO(4).
- To investigate the validity of a two-component description for this cuprate material.
- To challenge the widely accepted one-component model of cuprates.
Main Methods:
- Analysis of (63)Cu and (17)O NMR shift data.
- Modeling the data using a two-component system (A and B) with distinct magnetic susceptibilities (χ(AA), χ(AB), χ(BB)).
- Examining temperature dependence of susceptibilities above and below the critical temperature (T(c)).
Main Results:
- The analysis supports a two-component description of La(1.85)Sr(0.15)CuO(4).
- Magnetic susceptibilities χ(AB) and χ(BB) were found to be temperature-independent above T(c).
- The temperature dependence of all three susceptibilities above T(c) and combined susceptibilities below T(c) were determined.
Conclusions:
- The findings provide strong support for a two-component model of La(1.85)Sr(0.15)CuO(4).
- This contradicts the established one-component view of cuprate materials.
- The results align with theoretical proposals by Barzykin and Pines.
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