Strong electronic correlations in superconducting organic charge transfer salts

Abstract

We review the role of strong electronic correlations in quasi--two-dimensional organic charge transfer salts such as (BEDT-TTF)${}_{2}X$, (BETS)${}_{2}Y$ and ${\beta }^{\prime }$-[Pd(dmit)${}_2$]${}_{2}Z$. We begin by defining minimal models for these materials. It is necessary to identify two classes of material: the first class is strongly dimerised and is described by a half-filled Hubbard model; the second class is not strongly dimerised and is described by a quarter filled extended Hubbard model. We argue that these models capture the essential physics of these materials. We explore the phase diagram of the half-filled quasi--two-dimensional organic charge transfer salts, focusing on the metallic and superconducting phases. We review work showing that the metallic phase, which has both Fermi liquid and `bad metal' regimes, is described both quantitatively and qualitatively by dynamical mean field theory (DMFT). The phenomenology of the superconducting state is still a matter of contention. We critically review the experimental situation, focusing on the key experimental results that may distinguish between rival theories of superconductivity, particularly probes of the pairing symmetry and measurements of the superfluid stiffness. We then discuss some strongly correlated theories of superconductivity, in particular, the resonating valence bond (RVB) theory of superconductivity. We conclude by discussing some of the major challenges currently facing the field.

A review: 52 pages; 10 figs

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Cited by in corpus (44)

• The Hubbard model: A computational perspective
• Quantum frustration in organic Mott insulators: from spin liquids to unconventional superconductors
• Unified explanation of the Kadowaki-Woods ratio in strongly correlated materials
• Global phase diagrams of frustrated quantum antiferromagnets in two dimensions: doubled Chern-Simons theory
• Dynamics and transport of the Z_2 spin liquid: application to kappa-(ET)2Cu2(CN)3
• Quasiparticles at the verge of localization near the Mott metal-insulator transition in a two-dimensional material
• Importance of Spin-Orbit Coupling in Organic BEDT-TTF and BEDT-TSF Salts
• Symmetry of the superconducting order parameter in frustrated systems determined by the spatial anisotropy of spin correlations
• Competition between antiferromagnetic and charge order in the Hubbard-Holstein model
• Power-law dependence of the optical conductivity observed in the quantum spin-liquid compound κ-(BEDT-TTF)2Cu2(CN)3
• Electron-hole doping asymmetry of Fermi surface reconstructed in a simple Mott insulator
• Electron localization near Mott transition in organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2]$Br
• Towards the parameterisation of the Hubbard model for salts of BEDT-TTF: A density functional study of isolated molecules
• Optical probe of carrier doping by X-ray irradiation in organic dimer Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2]$Cl
• Field-induced staggered magnetic moment in the quasi-two-dimensional organic Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Cl
• Triangular lattice Hubbard model physics at intermediate temperatures
• Insulator-metal transition on the triangular lattice
• Excitation spectra and ground state properties of the layered spin-1/2 frustrated antiferromagnets Cs_2CuCl_4 and Cs_2CuBr_4
• Conditions for magnetically induced singlet d-wave superconductivity on the square lattice
• Spin liquid phase in the semiclassical theory of the Heisenberg model on an anisotropic triangular lattice with ring exchange
• Quantum critical transition from charge-ordered to superconducting state in the triangular lattice negative-U extended Hubbard model
• Two-dimensional ground-state mapping of a Mott-Hubbard system in a flexible field-effect device
• Temperature-driven transition from the Wigner Crystal to the Bond-Charge-Density Wave in the Quasi-One-Dimensional Quarter-Filled band
• Mixed order parameters, accidental nodes and broken time reversal symmetry in organic superconductors: a group theoretical analysis
• Antiferromagnetic Spin Fluctuations in the Metallic Phase of Quasi-Two-Dimensional Organic Superconductors
• Probing the Mott Physics in $\kappa$-(BEDT-TTF)${}_2$X Salts via Thermal Expansion
• Mott transition and superconductivity in the strongly correlated organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2]$Br
• Superconductivity and antiferromagnetism as interfering orders in organic conductors
• Mott transition and magnetism on the anisotropic triangular lattice
• Comprehensive $ab$ $initio$ investigation of the phase diagram of quasi-one-dimensional molecular solids
• Role of layer packing for the electronic properties of the organic superconductor (BEDT-TTF)${}_2$Ag(CF${}_3$)${}_4$(TCE)
• Superconductivity and Mottness in Organic Charge Transfer Materials
• Coherent heavy charge carriers in an organic conductor near the bandwidth-controlled Mott transition
• Thermodynamic Properties of the Mott Insulator-Metal Transition in a Triangular Lattice System Without Magnetic Order
• Vertex Corrections and the Korringa Ratio in Strongly Correlated Electron Materials
• Fulde-Ferrell-Larkin-Ovchinnikov state in strongly correlated d-wave superconductors
• Spin-singlet and spin-triplet pairing correlations in antiferromagnetically coupled Kondo systems
• Possible observation of the signature of the bad metal phase and its crossover to a Fermi liquid in K(BEDT-TTF)2Cu(NCS)2 bulk and nanoparticles by Raman scattering
• Preparation of Metal Mixed Plastic Superconductors: Electrical Properties of Tin-Antimony Thin Films on Plastic Substrates
• Nuclear Magnetic Resonance in Low-Symmetry Superconductors
• Charge glass in an extended dimer Hubbard model
• Electronic properties of the dimerized organic conductor $\kappa$-(BETS)${}_2$Mn[N(CN)${}_2$]${}_3$
• Disentangling real space fluctuations: the diagnostics of metal-insulator transitions beyond single-particle spectral functions
• Electronic correlations and spin frustration in the molecular conductors $\kappa$-(BEDT-TTF)${}_2$X probed by magnetic quantum oscillations