Near-degeneracy of extended $s+d_{x^2-y^2}$ and $d_{xy}$ order parameters in quasi-two-dimensional organic superconductors

Abstract

The symmetry of the superconducting order parameter in quasi-two-dimensional BEDT-TTF organic superconductors is a subject of ongoing debate. We report ab initio density functional theory calculations for a number of organic superconductors containing $\kappa$-type layers. Using projective Wannier functions we derive parameters of a common low-energy Hamiltonian based on individual BEDT-TTF molecular orbitals. In a random phase approximation spin-fluctuation approach we investigate the evolution of the superconducting pairing symmetry within this model and point out a phase-transition between extended $s+d_{x^2-y^2}$ and $d_{xy}$ symmetry. We discuss the origin of the mixed order parameter and the relation between the realistic molecule description and the widely used dimer approximation. Based on our ab initio calculations we position the investigated materials in the obtained molecule model phase diagram and simulate scanning tunneling spectroscopy experiments for selected cases. Our calculations show that many $\kappa$-type materials lie close to the phase transition line between the two pairing symmetry types found in our calculation, possibly explaining the multitude of contradictory experiments in this field.

References in corpus (52)

• A Common Thread: the pairing interaction for the unconventional superconductors
• Spin Liquid State in an Organic Mott Insulator with Triangular Lattice
• Near-degeneracy of several pairing channels in multiorbital models for the Fe-pnictides
• Iron-Based Superconductors: current status of materials and pairing mechanism
• Mott transition, antiferromagnetism, and unconventional superconductivity in layered organic superconductors
• Mott Transition from a Spin Liquid to a Fermi Liquid in the Spin-Frustrated Organic Conductor kappa-(ET)2Cu2(CN)3
• Similarities between organic and cuprate superconductors
• Unconventional critical behaviour in a quasi-two-dimensional organic conductor
• Nonmagnetic Insulating States near the Mott Transitions on Lattices with Geometrical Frustration and Implications for $\kappa$-(ET)${}_2$Cu${}_2(CN{)}_3$
• Multiferroicity in an organic charge-transfer salt: Electric-dipole-driven magnetism
• Pairing due to Spin Fluctuations in Layered Organic Superconductors
• Mott Transition, Antiferromagnetism, and d-wave Superconductivity in Two-Dimensional Organic Conductors
• Superconducting Gap Structure of kappa-(BEDT-TTF)2Cu(NCS)2 Probed by Thermal Conductivity Tensor
• Tight-binding models for the new iron based superconductor materials
• Revision of model parameters for kappa-type charge transfer salts: an ab initio study
• Ab initio Derivation of Low-Energy Model for $\kappa$-ET Type Organic Conductors
• Phase Diagram of Superconductivity on the Anisotropic Triangular Lattice Hubbard Model
• Cluster Dynamical Mean Field analysis of the Mott transition
• Strong electronic correlations in superconducting organic charge transfer salts
• Spin Fluctuation-Induced Superconductivity in Organic Compounds
• kappa-(BEDT-TTF)_2Cu[N(CN)_2]Br: a Fully Gapped Strong-Coupling Superconductor
• Specific heat measurements of the gap structure of the organic superconductors kappa-(ET)_2Cu[N(CN)_2]Br and kappa-(ET)_2Cu(NCS)_2
• Superconductivity and a Mott Transition in a Hubbard Model on an Anisotropic Triangular Lattice
• The effect of irradiation-induced disorder on the conductivity and critical temperature of the organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu(SCN)${}_2$
• d_{x^2-y^2}- vs. d_{xy}- like pairings in organic superconductors κ-(BEDT-TTF)_2 X
• High-resolution ac-calorimetry studies of the quasi-2D organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu(NCS)${}_2$
• Exact diagonalization study of Mott transition in the Hubbard model on an anisotropic triangular lattice
• Pairing and superconductivity driven by strong quasiparticle renormalization in two-dimensional organic charge transfer salts
• Absence of superconductivity in the half-filled band Hubbard model on the anisotropic triangular lattice
• Spin-liquid versus spiral-order phases in the anisotropic triangular lattice
• Pairing symmetry of the one-band Hubbard model in the paramagnetic weak-coupling limit: a numerical RPA study
• Pairing Symmetry Competition in Organic Superconductors
• Temperature dependence of structural and electronic properties of the spin-liquid candidate kappa-(BEDT-TTF)2Cu2(CN)3
• Unified picture of the doping dependence of superconducting transition temperatures in alkali metal/ammonia intercalated FeSe
• Electron localization near Mott transition in organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2]$Br
• Mott Transition and Phase Diagram of $\kappa$-(BEDT-TTF)2Cu(NCS)2 Studied by Two-Dimensional Model Derived from Ab initio Method
• Evidence for eight node mixed-symmetry superconductivity in a correlated organic metal
• Spin fluctuations and superconductivity in KxFe{2-y}Se2
• Purely electronic THz polarization in dimer Mott insulators
• Location of gap nodes in the organic superconductors $\kappa$-(ET)${}_2$Cu(NCS)${}_2$ and $\kappa$-(ET)${}_2$Cu[N(CN)${}_2$]Br determined by magnetocalorimetry
• Influence of molecular conformations on the electronic structure of organic charge transfer salts
• One-dimensional spin liquid, collinear, and spiral phases from uncoupled chains to the triangular lattice
• Mott metal-insulator transition induced by utilizing a glass-like structural ordering in low-dimensional molecular conductors
• Origin of the superconducting state in the collapsed tetragonal phase of KFe2As2
• In-plane superfluid density and microwave conductivity of the organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br: evidence for d-wave pairing and resilient quasiparticles
• Origin of the glass-like dynamics in molecular metals $\kappa$-(BEDT-TTF)${}_{\text{2}}$X: implications from fluctuation spectroscopy and $\text{ab initio}$ calculations
• Superconductor-Insulator Phase Separation Induced by Rapid Cooling in kappa-(ET)_2Cu[N(CN)_2]Br
• Antiferromagnetic Spin Fluctuations and the Pseudogap in the Paramagnetic Phases of Quasi-Two-Dimensional Organic Superconductors
• Antiferromagnetic Spin Fluctuations in the Metallic Phase of Quasi-Two-Dimensional Organic Superconductors
• Mixed pairing symmetry in κ-(BEDT-TTF)_2 X organic superconductors from ultrasonic velocity measurements
• Density of States and NMR Relaxation Rate in Anisotropic Superconductivity with Intersecting Line Nodes
• Role of layer packing for the electronic properties of the organic superconductor (BEDT-TTF)${}_2$Ag(CF${}_3$)${}_4$(TCE)

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• Fulde-Ferrell-Larkin-Ovchinnikov state induced by antiferromagnetic order in $\kappa$-type organic conductors
• From charge- and spin-ordering to superconductivity in the organic charge-transfer solids
• Evidence for electronically-driven ferroelectricity in the family of strongly correlated dimerized BEDT-TTF molecular conductors
• Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model
• Phase Competition and Superconductivity in $\kappa$-(BEDT-TTF)${}_2$X: Importance of Intermolecular Coulomb Interactions
• Superconductivity in correlated BEDT-TTF molecular conductors: critical temperatures and gap symmetries
• Altermagnetism on the Shastry-Sutherland lattice
• Two-dimensional ground-state mapping of a Mott-Hubbard system in a flexible field-effect device
• Mechanism of superconductivity and electron-hole doping asymmetry in $\kappa$-type molecular conductors
• Charge orders in organic charge-transfer salts
• Anisotropic Fully-Gapped Superconductivity Possibly Mediated by Charge Fluctuations in a Nondimeric Organic Complex
• Ingredients for Generalized Models of $\kappa$-Phase Organic Charge-Transfer Salts: A Review
• Electronic Structure Calculation and Superconductivity in $\lambda$-(BETS)${}_2$GaCl${}_4$
• Emergent anisotropy in the Fulde-Ferrell-Larkin-Ovchinnikov state
• Symmetry change of $d$-wave superconductivity in $\kappa$-type organic superconductors
• Mott transition and magnetism on the anisotropic triangular lattice
• Altermagnetism from coincident Van Hove singularities: application to $\kappa$-Cl
• Antiferromagnetic State in $\kappa$-type Molecular Conductors: Spin Splitting and Mott Gap
• Fate of the Hebel-Slichter peak in superconductors with strong antiferromagnetic fluctuations
• Thermodynamic Properties of the Mott Insulator-Metal Transition in a Triangular Lattice System Without Magnetic Order
• Microwave Conductivity Distinguishes Between Different d-wave States: Umklapp Scattering in Unconventional Superconductors
• Theory of triangular lattice quasi-one-dimensional charge-transfer solids
• Nuclear Magnetic Resonance in Low-Symmetry Superconductors
• Superconductivity in Sm-doped 1,3,5-triphenylbenzene
• Photoinduced Frustration Modulation in $\kappa$-type Quantum Spin Liquid Candidates
• Possibility of BCS-BEC crossover in $\kappa$-type organic superconductors