Diamagnetic susceptibility of spin-triplet ferromagnetic superconductors

Abstract

We calculate the diamagnetic susceptibility in zero external magnetic field above the phase transition from ferromagnetic phase to phase of coexistence of ferromagnetic order and unconventional superconductivity. For this aim we use generalized Ginzburg-Landau free energy of unconventional ferromagnetic superconductor with spin-triplet electron pairing. A possible application of the result to some intermetallic compounds is briefly discussed.Comment: 7 pages, 1 figur

Diamagnetic critical singularity in unconventional ferromagnetic superconductors

“…Here we consider for the first time the diamagnetic properties of 3D and q2D p-wave ferromagnetic superconductors -diamagnetic moment M and diamagnetic susceptibility χ dia . Some of our preliminary results for 3D (bulk) superconductors have been recently published [17]. We demonstrate that the diamagnetic susceptibility χ dia and diamagnetic moment M of p-wave ferromagnetic superconductors are dumped along the prevailing part of FM-FS phase transition line, in particular, at the second order phase transition line.…”

“…In the second equality (17) we point out the result of the summation over k x with the help of the rule (18). The obtained expression (17) follows from the fact that the mode energies E α (n, k z ) do not depend on the quantum number k x .…”

“…In the second equality (17) we point out the result of the summation over k x with the help of the rule (18). The obtained expression (17) follows from the fact that the mode energies E α (n, k z ) do not depend on the quantum number k x . Thus the number of states N at fixed quantum numbers n and k z and the relation F ∼ N are naturally deduced from the calculation.…”

Theory of Ferromagnetic Unconventional Superconductors with Spin-Triplet Electron Pairing

“…For ferromagnetic superconductors, where M > 0, one should use the magnetic induction B rather than H.IncaseofH = 0 one should apply the same criterion with respect to the magnetization M for small values of |ψ| near the phase transition line T c2 (M); M = |M|. For this reason we should use the diagonal quadratic form [35] corresponding to the entire ψ 2 -part of the total free energy functional (1). The lowest energy term in this diagonal quadratic part contains a coefficient a of the form a =(a s − γ 0 M − δM 2 ) [35].…”

“…For this reason we should use the diagonal quadratic form [35] corresponding to the entire ψ 2 -part of the total free energy functional (1). The lowest energy term in this diagonal quadratic part contains a coefficient a of the form a =(a s − γ 0 M − δM 2 ) [35]. Now the equation a(T)=0 defines the critical temperature of the Meissner phase and the equation |a s | = μ B M stands for T c2 (M).…”