Gap anisotropy, spin fluctuations, and normal-state properties of the electron-doped superconductor Sr0.9La0.1CuO2
UNSPECIFIED. (2002) Gap anisotropy, spin fluctuations, and normal-state properties of the electron-doped superconductor Sr0.9La0.1CuO2. PHYSICAL REVIEW B, 65 (22). -. ISSN 1098-0121Full text not available from this repository.
Official URL: http://dx.doi.org/10.1103/PhysRevB.65.224520
We report the results from a thermopower and a Cu nuclear magnetic resonance (NMR) study of the infinite-CuO2-layer electron-doped high-temperature superconducting cuprate (HTSC) Sr0.9La0.1CuO2. We find that the temperature dependence of the thermopower, S(T), is different from that observed in the hole-doped HTSC. In particular, we find that dS(T)/dT is positive above similar to120 K. However, we show that S(T) can still be described by the same model developed for the hole-doped HTSC and hence S(T) is not anomalous and does not imply phonon-mediated pairing as has previously been suggested. The Cu NMR data reveal a Knight shift and spin lattice relaxation rate below T-c that are inconsistent with isotropic s-wave pairing. The Cu spin lattice relaxation rate in the normal state, however, is Curie-Weiss like and is comparable to that of the optimally and overdoped hole-doped HTSC La2-xSrxCuO4. The magnitude of the Knight shift indicates that the density of states at the Fermi level is anomalously small when compared with the hole-doped HTSC with the same T-c, indicating that the size of N(E-f) is of little importance in the HTSC. We find no evidence of the normal state pseudogap that is observed in the hole-doped HTSC and which was recently reported to exist in the electron-doped HTSC Nd1.85Ce0.15CuO4 from infrared reflectance measurements.
|Item Type:||Journal Article|
|Subjects:||Q Science > QC Physics|
|Journal or Publication Title:||PHYSICAL REVIEW B|
|Publisher:||AMERICAN PHYSICAL SOC|
|Official Date:||1 June 2002|
|Number of Pages:||7|
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