Pseudo-gap phenomenon in the Sn-doped mercury-based cuprate superconductors

The Sn-doped mercury-based copper oxide high temperature superconductors, with nominal composition (Hg1-xSnx)Ba2Ca2Cu3O8+delta, have been successfully fabricated. These samples were used to study the pseudo-gap phenomenon in their normal phase. By means of ln[1/rho (T) - 1/rho (N)(T)] versus 1/T plots we found three characteristic temperatures T*, T-s, and TF, which describe the role of pseudo-gap phenomenon. From the stated plots, we are able to estimate the magnitude of the pseudo-gap for our samples. The pseudo-gap Delta (PG) changes into the spin pairing dipolar superconducting gap Delta (SPDS), when the Fermi kinetic energy shrinks to zero at the critical temperature T-c. It is proved that the spin pairing dipolar superconducting gap Delta (SPDS) = root (2/3)Delta (T), where, Delta (T) being the total superconducting gap of the cuprate superconductors, which has the value determined by 2 Delta (T) = 3.52 root 3k(B)T(c). It is also proved that the spin pairing dipolar superconducting gap is smaller than the dipolar pseudo-gap, Delta (PG).