Characterization of a Non-Superconducting Cuprate, Bi₂Sr₂YCu₂O_8.5

Abstract

A new Bi-containing cuprate, Bi 2 Sr 2 YCu 2 O 8.5 , was found in the course of substitution study for high T c compounds Bi 2 Sr 2 CaCu 2 O 8+ y . Bi 2 Sr 2 YCu 2 O 8.5 is a semiconductor and undergoes an antiferromagnetic transition at about 13 K which is considered to originate from the ordering of Cu in the CuO 2 planes. An electron diffraction study revealed the existence of a superstructure. The unit cell taking account of the superstructure is 1×8×1 of the original unit cell (5.47×5.43×30.18 Å 3 ). Analogy of three kinds of oxide systems, (La 1- x Sr x ) 2 CuO 4 , YBa 2 Cu 3 O 6+ x , and Bi 2 Sr 2 Ca x Y 1- x Cu 2 O 8+ y , is discussed.