We have measured the amplitude of the 1D lattice modulation forming the stripe structure in the CuO₂ plane of Bi₂Sr₂Ca₂Cu₂O_8+y single crystals by EXAFS. The period of the 1D modulation of the CuO₂ plane has been measured by Cu anomalous diffraction. The large anharmonic content of the 1D modulation clearly shows the formation of stripes of undistorted LTO lattice. The large amplitude of the local structure modulation in plane indicates the formation of sizable potential barrier due to the linear domain walls in the plane. The size of the stripes L is such that the Fermi level is tuned to the maximum of the density of states formed by the second subband. The tuning of the Fermi level at the shape resonance of the superlattice of quantum wires is proposed to be the mechanism for the amplification of the critical temperature in high T_c cuprate superconductors.

Date Published: 10 June 1996
PDF: 11 pages
Proc. SPIE 2696, Spectroscopic Studies of Superconductors, (10 June 1996); doi: 10.1117/12.241741

Published in SPIE Proceedings Vol. 2696:
Spectroscopic Studies of Superconductors
Ivan Bozovic; Dirk van der Marel, Editor(s)