Growth, structure and properties of Y2Cu2O5 single crystal

Growth, structure and physical properties of single crystals Y2Cu2O5, which is regarded as a family phase of the YBa2Cu3Oy high-temperature superconductor, have been investigated. Using the phase diagram of the Y2Cu2O5- (Cu2O+CuO) pseudo-binary system determined here, single crystals of Y2Cu2O5 have been obtained from a mixed solvent Cu2O+CuO. The obtained crystals are needle-shaped and the crystal system is orthorhombic with cell parameters a=10.814(1) A, b=12.480(2) A and c=3.5000(7) A, and space group Pn21a or Pnma. In the magnetic field parallel or perpendicular to the c-axis, the transition temperature TN of paramagnetic to antiferromagnetic state is around 13 K. In the field dependence of magnetization parallel to the c-axis, the antiferromagnetic state transits to a weakly ferromagnetic state above 30 kOe and then to the ferromagnetic state above 48 kOe. The hysteresis in the field transition is observed in the magnetization curve at 1.8 K.