FIELD DEPENDENCE OF THE PROPERTIES OF HIGH-TEMPERATURE SUPERCONDUCTORS

Abstract

High temperature superconductivity mechanism has remained an elusive concept for a long time. Field dependence of the properties of high temperature superconductors could be on the brink of solving this puzzle. This Study shows that there is a strong field dependence on the theory of high temperature superconductors (HTSCs). High temperature superconductors of transition temperature, 𝑇𝑐> 77 K (boiling point of liquid nitrogen) were studied. This research established that there are effects of applied magnetic field on a two dimensional square lattice, effective magnetic flux per plaquette and electric field on oscillating Cooper pairs parallel to copper oxide planes, and their effects on the thermodynamic properties of HTSCs. Second quantization formalism was used in determining the thermodynamic properties of HTSCs such as the energy gap and transition temperature. The effect of electric field E on an oscillating Cooper pair along the 𝐶𝑢𝑂2plane was found to give the value of Δ = 62.5 meV. The ratio (𝛼) of flux through the lattice cell to one flux quantum indicates that there is no Meissner expulsion of flux as the applied magnetic field H increases through the lattice cell. The value of 𝑇𝑐 at which superconductivity disappears was found to be 177K for YBCO/BSCCO systems. The lattice spacing a at 300Kwas 2.3Å. The value of 𝛼 was2.28 x 10−7 when 𝐻𝑐2 = 3.0 x 106G and a = 3Å.Studies on the effect of effective magnetic flux per plaquette Φ established that increase in values of Φ leads to increase in values of𝑇𝑐 and forΦ = 5.84𝐺/𝑚2, 𝑇𝑐 = 300K.