Bandwidth-controlled Mott transition in kappa-(BEDT-TTF)2Cu[N(CN)2]Br{x}Cl{1-x}: Optical studies of correlated carriers

Abstract

In the two-dimensional organic charge-transfer salts kappa-(BEDT-TTF)2Cu[N(CN)2]Br{x}Cl{1-x} a systematic variation of the Br content from x = 0 to 0.9 allows us to tune the Mott transition by increasing the bandwidth. At temperatures below 50 K, an energy gap develops in the Cl-rich samples and grows to approximately 1000 cm-1 for T -> 0. With increasing Br concentration spectral weight shifts into the gap region and eventually fills it up completely. As the samples with x = 0.73, 0.85 and 0.9 become metallic at low temperatures, a Drude-like response develops due to the coherent quasiparticles. Here, the quasiparticle scattering rate shows a omega^2 dependence and the effective mass of the carriers is enhanced in agreement with the predictions for a Fermi liquid. These typical signatures of strong electron-electron interactions are more pronounced for compositions close to the critical value x_c \approx 0.7 where the metal-to-insulator transition occurs.

arXiv comment11 pages, 12 figures

References in corpus (27)

• Mott transition, antiferromagnetism, and unconventional superconductivity in layered organic superconductors
• Cluster Dynamical Mean Field Theory of the Mott Transition
• Unconventional critical behaviour in a quasi-two-dimensional organic conductor
• Finite temperature numerical renormalization group study of the Mott-transition
• Pseudogap induced by short-range spin correlations in a doped Mott insulator
• Mott transition and transport crossovers in the organic compound $\kappa -(BEDT-TTF{)}_{2}Cu[N(CN{)}_2]Cl$
• Optical Conductivity in Mott-Hubbard Systems
• Mott Transition, Antiferromagnetism, and d-wave Superconductivity in Two-Dimensional Organic Conductors
• Transport properties of strongly correlated metals:a dynamical mean-field approach
• Constant effective mass across the phase diagram of high-T${}_c$ cuprates
• Transport criticality of the first-order Mott transition in a quasi-two-dimensional organic conductor, $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Cl
• Electrodynamics of the Nodal Metal in Weakly Doped High-$T_c$ Cuprates
• Bandwidth-controlled Mott transition in $\kappa -(BEDT-TTF{)}_{2}Cu[N(CN{)}_2]B{r}_{x}C{l}_{1-x}$ I. Optical studies of localized charge excitations
• 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
• Finite temperature Mott transition in Hubbard model on anisotropic triangular lattice
• 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
• Quasiparticles at the verge of localization near the Mott metal-insulator transition in a two-dimensional material
• Competition between Charge Ordering and Superconductivity in Layered Organic Conductors $\alpha$-(BEDT-TTF)${}_{2}M$Hg(SCN)${}_4$ (M = K, NH${}_4$)
• The Nature of Heavy Quasiparticles in Magnetically Ordered Heavy Fermions
• Magnetic-Field-Induced Mott Transition in a Quasi-Two-Dimensional Organic Conductor
• The Mott Metal-Insulator transition in the half-filled Hubbard model on the Triangular Lattice
• Electronic properties of correlated metals in the vicinity of a charge order transition: optical spectroscopy of $\alpha$-(BEDT-TTF)${}_{2}M$Hg(SCN)${}_4$ ($M$ = NH${}_4$, Rb, Tl)
• Correlation gap in the heavy-fermion antiferromagnet UPd_2Al_3
• Electrodynamics of correlated electron matter
• Optical probe of carrier doping by X-ray irradiation in organic dimer Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2]$Cl
• Phonon anomalies due to strong electronic correlations in layered organic metals
• Correlation gap in the optical spectra of the two-dimensional organic metal (BEDT-TTF)_4[Ni(dto)_2]

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