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.

arXiv commentA review: 52 pages; 10 figs

References in corpus (94)

• Quantum Cluster Theories
• Spin Liquid State in an Organic Mott Insulator with Triangular Lattice
• Superconductivity in the Intercalated Graphite Compounds C6Yb and C6Ca
• Imaging the granular structure of high-Tc superconductivity in underdoped Bi2Sr2CaCu2O8+x
• Imaging the Effects of Individual Zinc Impurity Atoms on Superconductivity in Bi2Sr2CaCu2O8+delta
• The Nernst effect in high-$T_c$ superconductors
• Long range Neel order in the triangular Heisenberg model
• Transport Properties, Thermodynamic Properties, and Electronic Structure of SrRuO3
• Variational study of triangular lattice spin-1/2 model with ring exchanges and spin liquid state in κ-(ET)_2 Cu_2 (CN)_3
• U(1) Gauge Theory of the Hubbard Model : Spin Liquid States and Possible Application to k-(BEDT-TTF)_2 Cu_2 (CN)_3
• Exact spectra, spin susceptibilities and order parameter of the quantum Heisenberg antiferromagnet on the triangular lattice
• Experimental realization of a 2D fractional quantum spin liquid
• Ab-initio theory of superconductivity - I: Density functional formalism and approximate functionals
• Universality and Critical Behavior at the Mott transition
• Interplay of magnetism and high-Tc superconductivity at individual Ni impurity atoms in Bi2Sr2CaCu2O8+d
• Similarities between organic and cuprate superconductors
• Ab-initio theory of superconductivity - II: Applications to elemental metals
• Finite temperature numerical renormalization group study of the Mott-transition
• Mott transition and transport crossovers in the organic compound $\kappa -(BEDT-TTF{)}_{2}Cu[N(CN{)}_2]Cl$
• Direct Measurement of the Spin Hamiltonian and Observation of Condensation of Magnons in the 2D Frustrated Quantum Magnet Cs2CuCl4
• On-chain electrodynamics of metallic (TMTSF)_2 X salts: Observation of Tomonaga-Luttinger liquid response
• Mott Transition, Antiferromagnetism, and d-wave Superconductivity in Two-Dimensional Organic Conductors
• Superconductivity mediated by charge fluctuations in layered molecular crystals
• Two spin liquid phases in the spatially anisotropic triangular Heisenberg model
• Superconducting Gap Structure of Spin-Triplet Superconductor Sr_2RuO_4 Studied by Thermal Conductivity
• Superconducting Gap Structure of kappa-(BEDT-TTF)2Cu(NCS)2 Probed by Thermal Conductivity Tensor
• Transport properties of strongly correlated metals:a dynamical mean-field approach
• Superconductivity in an organic insulator at very high magnetic fields
• Gap Structure of the Spin-Triplet Superconductor Sr2RuO4 Determined from the Field-Orientation Dependence of Specific Heat
• Cluster Dynamical Mean Field analysis of the Mott transition
• Phase diagram for a class of spin-half Heisenberg models interpolating between the square-lattice, the triangular-lattice and the linear chain limits
• Theoretical Aspects of Charge Ordering in Molecular Conductors
• Anisotropic thermodynamics of d-wave superconductors in the vortex state
• Magnetic ordering and spin waves in $\mathbf{N}{\mathbf{a}}_{0.82}\mathbf{Co}{\mathbf{O}}_2$
• Scaling of the quasiparticle spectrum for d-wave superconductors
• Observation of d-wave scaling relations in the mixed-state specific heat of YBa2Cu3O7
• kappa-(BEDT-TTF)_2Cu[N(CN)_2]Br: a Fully Gapped Strong-Coupling Superconductor
• Ultrasound Attenuation in Sr${}_2$RuO${}_4$: an Angle-Resolved Study of the Superconducting Gap Function
• Low Temperature Penetration depth of κ-(ET)_2Cu[N(CN)_2]Br and κ-(ET)_2Cu(NCS)_2
• Magnetic field - temperature phase diagram of quasi-two-dimensional organic superconductor lambda-(BETS)_2 GaCl_4 studied via thermal conductivity
• Dimerized phase and transitions in a spatially anisotropic square lattice antiferromagnet
• Vortex Contribution to Specific Heat of Dirty $d$-Wave Superconductors: Breakdown of Scaling
• Angular position of nodes in the superconducting gap of YBCO
• Anomalous superconducting state gap size versus Tc behavior in underdoped Bi_2Sr_2Ca_1-xDy_xCu_2O_8+d
• Anomalous Excitation Spectra of Frustrated Quantum Antiferromagnets
• Temperature Dependence of the Magnetic Susceptibility for Triangular-Lattice Antiferromagnets with spatially anisotropic exchange constants
• Ferromagnetic in-plane spin fluctuations in NaxCoO2 observed by neutron inelastic scattering
• Three-Dimensional Spin Fluctuations in Na0.75CoO2
• Anisotropy of magnetothermal conductivity in Sr2RuO4
• Finite-temperature dynamical magnetic susceptibility of quasi-one-dimensional frustrated spin-1/2 Heisenberg antiferromagnets
• Comparison of the phase diagram of the half-filled layered organic superconductors with the phase diagram of the RVB theory of the Hubbard-Heisenberg model
• Mott Transition, Compressibility Divergence and P-T Phase Diagram of Layered Organic Superconductors: An Ultrasonic Investigation
• The effect of irradiation-induced disorder on the conductivity and critical temperature of the organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu(SCN)${}_2$
• Ferromagnetism, paramagnetism and a Curie-Weiss metal in an electron doped Hubbard model on a triangular lattice
• Charge ordering and antiferromagnetic exchange in layered molecular crystals of the theta type
• High-resolution ac-calorimetry studies of the quasi-2D organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu(NCS)${}_2$
• Resistivity studies under hydrostatic pressure on a low-resistance variant of the quasi-2D organic superconductor kappa-(BEDT-TTF)2Cu[N(CN)2]Br: quest for intrinsic scattering contributions
• Non-generality of the Kadowaki-Woods ratio in correlated oxides
• Universality Classes of Metal-Insulator Transitions in Strongly Correlated Electron Systems and Mechanism of High-Temperature Superconductivity
• Pairing and superconductivity driven by strong quasiparticle renormalization in two-dimensional organic charge transfer salts
• Paramagnetic limiting of the upper critical field of the layered organic superconductor $\kappa -(BEDT-TTF{)}_{2}Cu(SCN{)}_2$
• The Dependence of the Superconducting Transition Temperature of Organic Molecular Crystals on Intrinsically Non-Magnetic Disorder: a Signature of either Unconventional Superconductivity or Novel Local Magnetic Moment Formation
• Large-N solutions of the Heisenberg and Hubbard-Heisenberg models on the anisotropic triangular lattice: application to Cs${}_2$CuCl${}_4$ and to the layered organic superconductors $\kappa$-(BEDT-TTF)${}_2$X
• Gossamer Superconductivity near Antiferromagnetic Mott Insulator in Layered Organic Conductors
• SU(2)-invariant spin-1/2 Hamiltonians with RVB and other valence bond phases
• The Heisenberg antiferromagnet on an anisotropic triangular lattice: linear spin-wave theory
• Magnetic-field-induced superconductivity in layered organic molecular crystals with localized magnetic moments
• Pairing Symmetry Competition in Organic Superconductors
• Criticality in quantum triangular antiferromagnets via fermionized vortices
• Dynamical mean field study of the Mott transition in the half-filled Hubbard model on a triangular lattice
• Real space imaging of the metal - insulator phase separation in the band width controlled organic Mott system $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Br
• The Mott Metal-Insulator transition in the half-filled Hubbard model on the Triangular Lattice
• Coupled Cluster Treatment Of An Interpolating Triangle/Kagome Antiferromagnet
• The gap equations for spin singlet and triplet ferromagnetic superconductors
• Elastic Study of Antiferromagnetic Fluctuations in the Layered Organic Superconductors kappa-(BEDT-TTF)_2X
• Sound Velocity Anomaly at the Mott Transition: application to organic conductors and V2O3
• Universal scaling relations in molecular superconductors
• Small-q phonon-mediated superconductivity in organic κ-BEDT-TTF compounds
• Ultrasound attenuation in gap-anisotropic systems
• BEDT-TTF organic superconductors: the entangled role of phonons
• Theory for Gossamer and Resonating Valence Bond Superconductivity
• Phonon anomalies due to strong electronic correlations in layered organic metals
• Finite-$U$ induced competing interactions, frustration, and quantum phase transition in a triangular-lattice antiferromagnet
• Quantum critical "opalescence" around metal-insulator transitions
• On the Relationship Between the Critical Temperature and the London Penetration Depth in Layered Organic Superconductors
• Superconductivity in Organic Compounds with Pseudo-Triangular Lattice
• Phase diagram and quasiparticle properties of the Hubbard model within cluster two-site DMFT
• Disordered, Spin Liquid and Valence-Bond Ordered Phases of the Kagome Lattice Quantum Ising Models With Transverse Field and XXZ Dynamics
• The effect of an in-plane magnetic field on the interlayer transport of quasiparticles in layered superconductors
• Quantum Mott Transition and Superconductivity
• Spin exchange and superconductivity in a $t-J^{\prime }-V$ model for two-dimensional quarter-filled systems
• Superconductivity and Antiferromagnetism in Quasi-one-dimensional Organic Conductors
• Superconductivity in Metal-mixed Ion-Implanted Polymer Films
• Competition between disorder and exchange splitting in superconducting ZrZn_2

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