X-ray diffraction measurements of the c-axis Debye-Waller factors of YBa2Cu3O7 and HgBa2CaCu2O6 -: art. no. 092508

We report an application of x rays to the measurement of the temperature-dependent Bragg peak intensities to obtain Debye-Waller factors on high-temperature superconductors. Intensities of (0,0,l) peaks of YBa2Cu3O7 and HgBa2CaCu2O6 thin films are measured to obtain the c-axis Debye-Waller factors. While lattice constant and some Debye-Waller factor measurements on high-T-c superconductors show anomalies at the transition temperature, our measurements by x-ray diffraction show a smooth transition of the c-axis Debye-Waller factors through T-c. This suggests that the dynamic displacements of the heavy elements along the c-axis direction in these compounds do not have anomalies at T-c. This method in combination with measurements by other techniques will give more details concerning the dynamics of the lattice.