A temperature-dependent study on a superconducting Bi2Sr2CaCu2Odeltasingle crystal by X-ray diffraction

The changes of profiles along the a, b and c directions of a Bi2Sr2CaCu2Odelta single crystal were examined by the X-ray diffraction method over the temperature range from 297 K to 77. Splitting of the (0k0) and (h00) diffraction peaks appeared in the temperature regions from 262 to 222 K and from 226 to 156 K, respectively. Changes of the modulation structure appear in the temperature regions from 207 to 202 K and from 112 to 102 K. Moreover, there is no remarkable change of the (00l) diffraction peaks. Below the temperature of 91 K, the (040) diffraction peak obviously begins to broaden.