Coexistence of ferromagnetism and superconductivity: the role of kinetic interactions, kinetic correlations, and external pressure

Abstract

We use the Hubbard type model to describe the coexistence between superconductivity (SC) and ferromagnetism (F). Our Hamiltonian contains single-site and two-site interactions. All inter-site interactions will have included the inter-site kinetic correlation: $<c_{i\sigma }^{+}{c}_{j\sigma }>$, within the Hartree-Fock approximation. To obtain the SC transition temperature $T_{SC}$ and Curie temperature $T_C$ we use the Green's functions method. The numerical results show that the singlet SC is eliminated by F, but the triplet SC is either enhanced or depleted by F, depending on the carrier concentration and direction of a superconducting spin pair with respect to magnetization. The kinetic correlation is capable of creating superconductivity. We find that the ferromagnetism created by change of the bandwidth can coexist with singlet superconductivity. In the case of triplet superconductivity the ferromagnetism creates different critical SC temperatures for the $A_1$ and $A_2$ phase (the pair's spin parallel and antiparallel to magnetization, respectively).

arXiv comment15 pages, 9 figures

References in corpus (14)

• Coexistence of ferromagnetism and superconductivity in the hybrid ruthenate-cuprate compound RuSr_2GdCu_2O_8 studied by muon spin rotation (μSR) and DC-magnetization
• First order transitions and multicritical points in weak itinerant ferromagnets
• Theory of Ferromagnetic Superconductivity
• A Model for Superconductivity in Ferromagnetic ZrZn2
• Competition of Spin-Fluctuations and Phonons in Superconductivity of ZrZn2
• Longitudinal spin-fluctuations and superconductivity in ferromagnetic ZrZn${}_2$ from ab initio calculations
• Metallic ferromagnetism without exchange splitting
• The gap equations for spin singlet and triplet ferromagnetic superconductors
• Coexistence of ferromagnetism and singlet superconductivity via kinetic exchange
• Breakdown of the coexistence of spin-singlet superconductivity and itinerant ferromagnetism
• d-wave superconductivity in a generalized Hubbard model
• Superconductivity with s and p-symmetries in an extended Hubbard model with correlated hopping
• Magnetic ordering of itinerant systems; the role of kinetic exchange interaction
• Magnetic Ordering of Itinerant Systems in Modified CPA Approximation

Cited by in corpus (1)

• Coexistence of two vector order parameters: a holographic model for ferromagnetic superconductivity