Abstract:
The study explores the impact of spin fluctuation on the superconductivity of the
Gd1−xThxFeAsO superconductor through a theoretical investigation. Employing a model
Hamiltonian, which accounts for the interplay between superconductivity and magnetism
within the material, the study incorporates spin exchange interactions attributed to localized
electrons. This theoretical framework is solved using the equation of motion approach within
Green’s function formalism. Theoretical expressions are derived to elucidate the relationship
between key parameters such as the superconducting critical temperature (Tc), superconducting
order parameter ( ), and magnetic transition temperature (Tm) concerning the
strength of interaction between Cooper paired electrons and magnetic ordering strength.
Notably, the results reveal a nuanced relationship where an increase in phonon-mediated
coupling interaction strength leads to a rise in the superconducting critical temperature,
while an increase in antiferromagnetic ordering strength results in the suppression of Tc.
These findings provide valuable insights into the intricate interplay between spin fluctuations
and superconductivity in Gd1−xThxFeAsO, thus contributing to the understanding of the
mechanisms underlying high-temperature superconductivity in this system
