TSFZ GROWTH OF ND2-XCEXCUO4 SINGLE-CRYSTALS AT LOW-OXYGEN PRESSURE

Nd(1.8)5Ce(0.15)CuO(4) single crystals of improved quality were grown by TSFZ method at low oxygen partial pressure of 0.2, 0.1, 0.08 and 0. 01 atm. Superconductivity in as-grown state was observed in the crysta ls grown at 0.08 and 0.01 atm. The improvement of Ce distribution was achieved due to decreased value of Ce distribution coefficient at low oxygen partial pressure in ambient atmosphere. The probability to obta in the same characteristics of the superconducting transition in as-gr own state as that in the crystals after post-growth high temperature t reatment seems to be very low because of oxidation during the cooling of the grown crystals from the crystallization temperature to the room temperature.