Enhanced superconducting properties of Cu0.5(Tl0.5−yHgy)Ba2Ca3Cu4O12−δ (y = 0, 0.15, 0.25, 0.35) superconductor

The superconducting properties of Cu0.5(Tl0.5−yHgy)Ba2Ca3Cu4O12−δ compound have been studied by resistivity and AC magnetic susceptibility measurements. Mercury substitution has been found to improve the interlayer coupling in the unit cell of Cu0.5(Tl0.5−yHgy)Ba2Ca3Cu4O12−δ superconductor which is witnessed from the enhancement of superconducting properties like zero resistivity critical temperature, critical current density and flux pinning. The AC susceptibility measurements under different DC magnetic fields show that Cu0.5(Tl0.25Hg0.25)-1234 has superior flux pinning characteristics as compared to Cu1−xTlx-1234 which make them useful for applications in external magnetic fields.