Preparation of single crystals of superconducting YBa2Cu3O7−<i>x</i> from CuO melts

Abstract

Millimeter size single crystals of superconducting YBa2Cu3O7−x (Tc ∼90 K) were grown by melting a mixture of stoichiometric YBa2Cu3O7−x plus excess CuO at 1150 °C followed by holding at 900 °C for four days. Crystals were in the form of plates with c axis normal to the plate face. Growth of the crystals is believed to be aided by a liquid phase which is present at the holding temperature.