La1-xSrxCuO2.5 representing a hole-doped spin ladder system

La1-xSrxCuO2.5 presents a hole-doped spin ladder compound. Because of relat ively strong interladder interactions the insulating parent compound LaCuO2 .5 exhibits antiferromagnetic order below 120 K instead of a spin liquid gr ound state expected for isolated, or weakly coupled spin ladders. Supercond uctivity has not been detected upon hole doping in La1-xSrxCuO2.5, though a gradual insulator-metal transition was observed. Recent experimental resul ts suggest that the system tends to be phase-separated. (C) 1999 Elsevier S cience B.V. All rights reserved.