Synthesis of the electron-doped copper superconductors Eu$_{2-x}$Ce$_{x}$CuO$_{4-y}$ and their physical property characterization using the X-ray powder diffraction and high pressure*

The electron-doped copper superconductors Eu$_{2-x}$Ce$_{x}$CuO$_{4-y}$ (0 $\leq$ $x$ $\leq$ 0.25 ) were synthesized successfully using a solid state reaction method under a series of annealing and reduction procedures. X-ray diffraction and high hydrostatic pressure were used for their structure and electrical property characterization. Preliminary results show that the samples are in a single phase and the T$_{c}$ drops as the pressure increases with a rate in sign opposite to the hole-doped counterparts and in magnitude apparently smaller than other cuprate superconductors.