Interplay Between Superconductivity and Antiferromagnetism in HoNi2B2C

Abstract

A microscopic theory of interplay between superconductivity and antiferromagnetism in rare-earth nickel boride, HoNi2B2C is developed from first principles. Self-consistent equations for the superconducting order parameter Δ and magnetic order parameter Γ are derived using a Green’s function technique and an equation of motion method. The theory is applied to explain the experimental results in the antiferromagnetic superconductor HoNi2B2C. The present model explains the true coexistence of superconductivity and antiferromagnetism in this system. The behavior of the superconducting order parameter (Δ), the magnetic order parameter (Γ), the specific heat, the density of states, the free energy and critical field (Hc) is also studied for the system HoNi2B2C. Distinct features of the coexistence region are discussed. There is the convincing evidence that the theory is fully compatible with the key experiments.