Anomalous dielectric response in the dimer Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu${}_2$(CN)${}_3$

Abstract

We have measured and analyzed the dielectric constant of the dimer Mott insulator $\kappa -$(BEDT-TTF)${}_2$Cu${}_2$(CN)${}_3$, which is known as a playground for a spin-liquid state. Most unexpectedly, this particular organic salt has nontrivial charge degrees of freedom, being characterized by a dipole-glass-like dielectric relaxation below around 60 K. This is ascribed to the charge disproportionation within the dimer due to the intersite Coulomb repulsion. In this respect, the dipole observed here is purely quantum mechanical, and thereby exhibits unexpected responses.

5 pages, 5 figures

References in corpus (9)

• 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
• Theoretical Aspects of Charge Ordering in Molecular Conductors
• Emergence of inhomogeneous moments from spin liquid in the triangular-lattice Mott insulator $\kappa$-(ET)${}_2$Cu${}_2$(CN)${}_3$
• Lattice effects and entropy release at the low-temperature phase transition in the spin-liquid candidate $\kappa$-(BEDT-TTF)${}_2$Cu${}_2$(CN)${}_3$
• 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
• The Paired-Electron Crystal in the Two-Dimensional Frustrated Quarter-Filled Band
• Effective Coulomb interactions within BEDT-TTF dimers
• Bipolaron Density-Wave Driven By Antiferromagnetic Correlations and Frustration in Organic Superconductors

Cited by in corpus (77)

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• Absence of charge order in the dimerized κ-phase BEDT-TTF salts
• Static and dynamical spin correlations of the S=1/2 random-bond antiferromagnetic Heisenberg model on the triangular and the kagome lattices
• The Paired Electron Crystal: order from frustration in the quarter-filled band
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• Gapped magnetic ground state in quantum-spin-liquid candidate $\kappa$-(BEDT-TTF)${}_2$-Cu${}_2$(CN)${}_3$
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• Anisotropic charge dynamics in the quantum spin-liquid candidate $\kappa$-(BEDT-TTF)${}_2$Cu${}_2$(CN)${}_3$
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• Critical Spin Liquid versus Valence Bond Glass in Triangular Lattice Organic $\kappa$-(ET)${}_2$Cu${}_2$(CN)${}_3$
• Rearrangement of Van-der-Waals Stacking and Formation of a Singlet State at $T=90$ K in a Cluster Magnet
• Collective excitation of electric dipole on molecular dimer in organic dimer-Mott insulator
• Molecular Quantum Materials: Electronic Phases and Charge Dynamics in Two-Dimensional Organic Solids
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• Relaxor ferroelectricity induced by electron correlations in a molecular dimer Mott insulator
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• Randomness-induced quantum spin liquid behavior in the $s=$1/2 bond-random Heisenberg antiferromagnet on the pyrochlore lattice
• Mott Transition and Phase Diagram of $\kappa$-(BEDT-TTF)2Cu(NCS)2 Studied by Two-Dimensional Model Derived from Ab initio Method
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• Microscopic phase separation in triangular-lattice quantum spin magnet kappa-(BEDT-TTF)2Cu2(CN)3 probed by muon spin relaxation
• Collective Charge Excitation in a Dimer Mott Insulating System
• Phase Competition and Superconductivity in $\kappa$-(BEDT-TTF)${}_2$X: Importance of Intermolecular Coulomb Interactions
• Quantum Paraelectricity in the Kitaev Quantum-Spin-Liquid Candidates H${}_3$LiIr${}_2$O${}_6$ and D${}_3$LiIr${}_2$O${}_6$
• Low-Temperature Dielectric Anomalies at the Mott Insulator-Metal Transition
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• Polar Charge Fluctuation and Superconductivity in Organic Conductor
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• Griffiths-like phase close to the Mott transition
• Coulomb enhancement of superconducting pair-pair correlations in a $\frac{3}{4}$-filled model for $\kappa$-(BEDT-TTF)${}_2$X
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• Ingredients for Generalized Models of $\kappa$-Phase Organic Charge-Transfer Salts: A Review
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