Multiferroicity in an organic charge-transfer salt: Electric-dipole-driven magnetism

Abstract

Multiferroics, showing simultaneous ordering of electrical and magnetic degrees of freedom, are remarkable materials as seen from both the academic and technological points of view. A prominent mechanism of multiferroicity is the spin-driven ferroelectricity, often found in frustrated antiferromagnets with helical spin order. There, similar to conventional ferroelectrics, the electrical dipoles arise from an off-centre displacement of ions. However, recently a different mechanism, namely purely electronic ferroelectricity, where charge order breaks inversion symmetry, has attracted considerable interest. Here we provide evidence for this exotic type of ferroelectricity, accompanied by antiferromagnetic spin order, in a two-dimensional organic charge-transfer salt, thus representing a new class of multiferroics. Quite unexpectedly for electronic ferroelectrics, dipolar and spin order arise nearly simultaneously. This can be ascribed to the loss of spin frustration induced by the ferroelectric ordering. Hence, here the spin order is driven by the ferroelectricity, in marked contrast to the spin-driven ferroelectricity in helical magnets.

8 pages, 9 figures (including 4 pages and 6 figures in supplementary information). Version 2 with minor errors corrected (legend of Fig. 3c and definition of vectors e and Q)

References in corpus (16)

• Spin current and magneto-electric effect in non-collinear magnets
• Ferroelectricity in spiral magnets
• Role of the Dzyaloshinskii-Moriya interaction in multiferroic perovskites
• Spin Liquid State in an Organic Mott Insulator with Triangular Lattice
• Colossal dielectric constants in transition-metal oxides
• Multiferroicity due to charge ordering
• Mott transition, antiferromagnetism, and unconventional superconductivity in layered organic superconductors
• Charge ordering in the TMTTF family of molecular conductors
• 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
• Anomalous dielectric response in the dimer Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu${}_2$(CN)${}_3$
• Switching the Ferroelectric Polarization by External Magnetic Fields in the Spin = 1/2 Chain Cuprate LiCuVO4
• The Paired-Electron Crystal in the Two-Dimensional Frustrated Quarter-Filled Band
• Evidence for Lattice Effects at the Charge-Ordering Transition in (TMTTF)${}_2$X
• Relaxor ferroelectricity and the freezing of short-range polar order in magnetite
• Slowing down of the relaxational dynamics at the ferroelectric phase transition in one-dimensional (TMTTF)2AsF6

Cited by in corpus (67)

• Electrical control of magnetism by electric field and current-induced torques
• Absence of charge order in the dimerized κ-phase BEDT-TTF salts
• Spin-liquid versus spiral-order phases in the anisotropic triangular lattice
• Importance of Spin-Orbit Coupling in Organic BEDT-TTF and BEDT-TSF Salts
• Phase diagram and collective excitation in excitonic insulator: from the orbital physics viewpoint
• Molecular Quantum Materials: Electronic Phases and Charge Dynamics in Two-Dimensional Organic Solids
• Determination of intrinsic ferroelectric polarization in lossy improper ferroelectric systems
• Ferroelectricity from iron valence ordering in rare earth ferrites?
• Power-law dependence of the optical conductivity observed in the quantum spin-liquid compound κ-(BEDT-TTF)2Cu2(CN)3
• Relaxor ferroelectricity induced by electron correlations in a molecular dimer Mott insulator
• From charge- and spin-ordering to superconductivity in the organic charge-transfer solids
• Near-degeneracy of extended $s+d_{x^2-y^2}$ and $d_{xy}$ order parameters in quasi-two-dimensional organic superconductors
• Evidence for electronically-driven ferroelectricity in the family of strongly correlated dimerized BEDT-TTF molecular conductors
• Dielectric Spectroscopy on Organic Charge-Transfer Salts
• Polar Dynamics at the Jahn-Teller Transition in Ferroelectric GaV4S8
• Anions effects on the electronic structure and electrodynamic properties of the Mott insulator $\kappa$-(BEDT-TTF)${}_2$Ag${}_2$(CN)${}_3$
• Ferroelectric properties of charge-ordered alpha-(BEDT-TTF)2I3
• Charge-Transfer Dynamics and Nonlocal Dielectric Permittivities Tuned with Metamaterial Structures as Solvent Analogues
• Prediction of Intrinsic Triferroicity in Two-Dimensional Lattice
• Influence of molecular conformations on the electronic structure of organic charge transfer salts
• Polar and magnetic order in GaV4Se8
• $ab$-$initio$ Approaches for Low-Energy Spin Hamiltonians
• Low-Temperature Dielectric Anomalies at the Mott Insulator-Metal Transition
• Impurity Moments Conceal Low-Energy Relaxation of Quantum Spin Liquids
• Origin of the glass-like dynamics in molecular metals $\kappa$-(BEDT-TTF)${}_{\text{2}}$X: implications from fluctuation spectroscopy and $\text{ab initio}$ calculations
• Charge order textures induced by non-linear lattice coupling in a half-doped manganite
• Charge-Ordering Transition in (TMTTF)${}_2$X Explored via Dilatometry
• Metal-Insulator Transition in the Dimerized Organic Conductor $\kappa$-(BEDT-TTF)${}_2$Hg(SCN)${}_2$Br
• Polar Charge Fluctuation and Superconductivity in Organic Conductor
• Interplay of dipoles and spins in $\kappa$-(BEDT-TTF)${}_{2}X$, where $X=$ Hg(SCN)${}_2$Cl, Hg(SCN)${}_2$Br, Cu[N(CN)${}_2$]Cl, Cu[N(CN)${}_2$]Br, and Ag${}_2$(CN)${}_3$
• Crystal Growth of new charge-transfer salts based on $\pi$-conjugated molecules
• Orbital-Order Driven Ferroelectricity and Dipolar Relaxation Dynamics in Multiferroic GaMo${}_4$S${}_8$
• Correlation-driven electronic multiferroicity in (TMTTF)${}_2$-$X$ organic crystals
• Coulomb enhancement of superconducting pair-pair correlations in a $\frac{3}{4}$-filled model for $\kappa$-(BEDT-TTF)${}_2$X
• Electron spin dynamics of two-dimensional layered materials
• Charge orders in organic charge-transfer salts
• Phase coexistence at the first-order Mott-transition revealed by pressure-dependent dielectric spectroscopy of $\kappa$-(BEDT-TTF)${}_2$Cu${}_2$(CN)${}_3$
• Multiferroicity in the Mott Insulating Charge-Transfer Salt κ-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Cl
• Evolution of ferroelectricity in tetrathiafulvalene-p-chloranil as a function of pressure and temperature
• Charge disproportionation in the spin-liquid candidate $\kappa$-(ET)${}_2$Cu${}_2$(CN)${}_3$ at 6 K revealed by ${}^{63}$Cu NQR measurements
• Probing the Mott Physics in $\kappa$-(BEDT-TTF)${}_2$X Salts via Thermal Expansion
• Ingredients for Generalized Models of $\kappa$-Phase Organic Charge-Transfer Salts: A Review
• Optical Conductivity Measurement of a Dimer-Mott to Charge-Order Phase Transition in a Two-Dimensional Quarter-Filled Organic Salt Compound
• Electronic ferroelectricity in carbon based materials
• Insights from experiment and $abinitio$ calculations into the glass-like transition in the molecular conductor $\kappa$-(BEDT-TTF)${}_2$Hg(SCN)${}_2$Cl
• Quantum Melting of Magnetic Order in an Organic Dimer-Mott Insulating System
• Lattice dynamics coupled to charge and spin degrees of freedom in the molecular dimer-Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Cl
• Ferromagnetism out of charge fluctuation of strongly correlated electrons in $\kappa$-(BEDT-TTF)${}_2$Hg(SCN)${}_2$Br
• Antipolar transitions in GaNb${}_4$Se${}_8$ and GaTa${}_4$Se${}_8$
• Antiferromagnetic State in $\kappa$-type Molecular Conductors: Spin Splitting and Mott Gap
• Phonon-Spectrum Narrowing Induced by Ultrafast Charge Fluctuation in an Organic Dimer Mott Insulator
• Coherent heavy charge carriers in an organic conductor near the bandwidth-controlled Mott transition
• High temperature non-collinear magnetism in a classical bilinear-biquadratic Heisenberg model
• Strong ferromagnetic fluctuations in a doped checkerboard lattice
• Incipient spin-dipole coupling in a 1D helical-chain metal-organic hybrid
• Relaxation dynamics in the one-dimensional organic charge-transfer salt δ-(EDT-TTF-CONMe${}_2$)${}_2$Br
• Electronic State and Optical Response in a Hydrogen-Bonded Molecular Conductor
• Spin and Charge Fluctuations near Metal-Insulator Transition in Dimer-Type Molecular Solid
• Localized states in the Mott insulator κ-(BEDT-TTF)_2Cu[N(CN)_2]Cl as probed by photoluminescence
• Evidence for distortion-induced local electric polarization in $\alpha$-RuCl${}_3$
• Realization of anomalous multiferroicity in free-standing graphene with magnetic adatoms
• Rényi entropy of quantum anharmonic chain at non-zero temperature
• Character of frustration on magnetic correlation in doped Hubbard model
• Surface magnetism of gallium arsenide nanofilms
• Electronic correlations and spin frustration in the molecular conductors $\kappa$-(BEDT-TTF)${}_2$X probed by magnetic quantum oscillations
• Effect of electromagnetic permeability on transition temperature of superconductivity
• Spin liquid and ferroelectricity close to a quantum critical point in PbCuTe${}_2$O${}_6$