2006/10/31 by Guillaume Roux, G. Roux, E. Orignac +4
Materials Science · Physics and Astronomy · #Iron-based superconductors research #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.75.245119
published as Phys. Rev. B 75, 245119 (2007) · 18 pages, 19 figures
openalex publication_date 2007/06/20 · arxiv created 2007/06/25 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We review the properties of two coupled fermionic chains, or ladders, under a magnetic field parallel to the lattice plane. Results are computed by complementary analytical (bosonization) and numerical (density-matrix renormalization group) methods, which allows a systematic comparison. Limiting cases such as coupled-band and coupled-chain regimes are discussed. We particularly focus on the evolution of the superconducting correlations under increasing field and on the presence of irrational magnetization plateaus. We found the existence of large doping-dependent magnetization plateaus in the weakly interacting and strong-coupling limits and in the nontrivial case of isotropic couplings. We report on the existence of extended Fulde-Ferrell-Larkin-Ovchinnikov phases [Phys. Rev. 135, A550 (1964); Sov. Phys. JETP 20, 762 (1965);] within the isotropic t\text\ensuremath-J and Hubbard models, deduced from the evolution of different observables under magnetic field. Emphasis is put on the variety of superconducting order parameters present at high magnetic field. We have also computed the evolution of the Luttinger exponent corresponding to the ungapped spin mode appearing at finite magnetization. In the coupled-chain regime, the possibility of having polarized triplet pairing under high field is predicted by bosonization.