| EPSRC Reference: |
GR/L77546/01 |
| Title: |
OXYGEN ISOTAPE EFFECT IN THE NORMAL-STATE PSEUDOGAP OF HIGH-TC SUPERCONDUCTORS |
| Principal Investigator: |
Liang, Professor W |
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| Department: |
Superconductivity (IRC) |
| Organisation: |
University of Cambridge |
| Scheme: |
Standard Research (Pre-FEC) |
| Starts: |
01 September 1997 |
Ends: |
31 January 1998 |
Value (£): |
9,058
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| No relevance to Underpinning Sectors |
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Summary on Grant Application Form |
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The complex isotope effects in HTS cuprates is not understood. Isotope studies progressing deep into the overdoped region or on the pseudogap have not hitherto been carried out. Key information to assist in understanding the nature of the pseudogap and of the pairing interaction is therefore lacking. High quality samples of Yba2Cu4O8 and Yo.8CaO.2Ba2Cu3O7-8 will be synthesized. Through proper processing the latter samples can be heavily overdoped to Tc=45K and by progressive unloading underdoped to Tc=35K thus allowing isotope studies over broad doping range. 18O exchanged and unexchanged samples will be investigated using magnetometry, heat capacity and 89Y NMR spectroscopy. Site specific exchange will be confirmed by Raman investigation of phonon mode frequencies. The heat capacity and NMR studies will allow the pseudogap energy to be determined through modelling the entropy and Knight shift. Both techniques have sufficient sensitivity to detect a pseudogap isotope effect at the level of alpha>0.015. Through a knowledge of the isotope effect in Tc and the isotope effect in the pseudogap energy the isotope effect in the superconducting gap, --, may be determined which is a more fundamental property. Only then can the role of phonons in both superconductivity and the pseudogap be assessed.
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Key Findings |
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This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
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Potential use in non-academic contexts |
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This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
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Impacts |
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| Description |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk |
| Summary |
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| Date Materialised |
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Sectors submitted by the Researcher |
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This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
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| Project URL: |
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| Further Information: |
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| Organisation Website: |
http://www.cam.ac.uk |