Triplet superconductivity in coupled odd-gon rings

Abstract

Shedding light on the nature of spin-triplet superconductivity has been a long-standing quest of solid-state physics since the discovery of superfluidity in liquid ${}^3$He. Nevertheless, the mechanism of spin-triplet pairing is much less understood than that of spin-singlet pairing explained by the Bardeen-Cooper-Schrieffer theory or even observed in high-temperature superconductors. Here we propose a versatile mechanism for spin-triplet superconductivity, which is mediated through a melting of macroscopic spin polarization in weakly coupled odd-gon-unit system (e.g., triangular unit, pentagon unit, etc). We demonstrate the application of this mechanism by considering a new class of quasi-one-dimensional superconductors A${}_2$Cr${}_3$As${}_3$ (A=K, Rb, and Cs). Furthermore, we derive a simple effective Hamiltonian to easily illustrate the adaptability of the mechanism to general coupled odd-gon-unit systems. We thus argue that materials consisting of odd-numbered geometric units would be a prospect of spin-triplet superconductivity.

12 pages, 5 figures + SUPPLEMENTARY INFORMATION

References in corpus (14)

• Superconductivity in quasi-one-dimensional K${}_2$Cr${}_3$As${}_3$ with significant electron correlations
• Unconventional superconductivity in quasi-one-dimensional Rb${}_2$Cr${}_3$As${}_3$
• Superconductivity in quasi-one-dimensional Cs2Cr3As3 with large interchain distance
• p-wave triggered superconductivity in single layer graphene on an electron-doped oxide superconductor
• Frustrated three-leg spin tubes: from spin 1/2 with chirality to spin 3/2
• Spin singlet pairing in the superconducting state of NaxCoO2\cdot1.3H2O: evidence from a ^{59}Co Knight shift in a single crystal
• Direct penetration of spin-triplet superconductivity into a ferromagnet in Au/SrRuO3/Sr2RuO4 junctions
• Multiband one-dimensional electronic structure and spectroscopic signature of Tomonoga-Luttinger liquid behavior in K${}_2$Cr${}_3$As${}_3$
• Magnetization-control and transfer of spin-polarized Cooper pairs into a half-metal manganite
• Symmetries of the quasi-1d Bechgaard salts superconducting state in an applied magnetic field
• Magnetic field induced singlet - triplet phase transition in quasi one-dimensional organic superconductors
• Magnetic exchange fields and domain wall superconductivity at an all-oxide superconductor / ferromagnet insulator interface
• Ring Exchange Mechanism for Triplet Superconductivity in a Two-Chain Hubbard Model: Possible Relevance to Bechgaard Salts
• Co-NMR Knight Shift of NaxCoO2 \dot yH2O Studied in Both Superconducting Regions of the Tc-nuQ3 Phase Diagram Divided by the Nonsuperconducting Phase

Cited by in corpus (5)

• Spin and charge density waves in the quasi-one-dimensional KMn6Bi5
• Intra-chain collinear magnetism and inter-chain magnetic phases in Cr3As3-K-based materials
• Spin-$0$ Mott insulator to metal to spin-$1$ Mott insulator transition in the single-orbital Hubbard model on the decorated honeycomb lattice
• Multiple insulating phases due to the interplay of strong correlations and lattice geometry in a single-orbital Hubbard model
• Multiple phases in K2Cr3As3: a playground for manipulating topological superconductivity