Naslov
Evidence for an axial oxygen-centered lattice fluctuation associated with the superconducting transition in YBa2Cu3O7

Autori
Mustre de Leon, Jose ; Conradson, S.D. ; Batistić, Ivo ; Bishop, Alan R.

Izvornik
Physical review letters (0031-9007) 65 (1990), 13; 1675-1678

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
high temperature superconductors ; axial O centered lattice fluctuation ; EXAFS

Sažetak
The axial oxygen contributions to the Cu K-edge, polarized, extended X-ray absorption fine structure of YBa/sub 2/Cu/sub 3/O/sub 7/ are analyzed for 10[left angle bracket]or=T[left angle bracket]or=105 K, using a novel approach in which the radial distribution function is directly calculated from model potentials. The best fit is obtained with a double-well potential with two nearly equally populated O(4) sites 0.13 AA apart. The site separation decreases 0.02 AA in a region near T/sub c/. This perturbation of the structure is accompanied by a large increase of the tunneling frequency of approximately 80 K between the two wells, suggesting a coupling between superconducting fluctuations and nonlinear phonons.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA