Y-Ba-Cu-O系超伝導体と電気光学結晶との反応性

We investigated the reactivity of YBa2Cu3Oy (YBCO) with electrooptic crystals, such as LiNbO3 (LN), LiTaO3 (LT), Sr0.75Ba0.25Nb2O6 (SBN), KTa0.65Nb0.35O3 (KTN), Ba2NaNb5O15 (BNN). The YBCO powder mixed with 5wt% electrooptic crystal was heated at 700°C for 8hr, 16hr or at 900°C for 8hr in air. The reactivity of LT, LN, KTN with YBCO was considerably high, and that of BNN was relativly low.The YBCO thin films were deposited on LN and BNN substrates through an RF magnetron sputtering method. The YBCO thin films on BNN were c-axes oriented with Tc(zero)=72.5K and c=11.70A. The thickness of the reaction layer for BNN was one order of magnitude thinner than that for LN. From these results, the BNN single crystal was concluded to be suitable for an electrooptic substrate for YBCO thin film fabrication.