Optical probe of carrier doping by X-ray irradiation in organic dimer Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2]$Cl

Abstract

We investigated the infrared optical spectra of an organic dimer Mott insulator $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Cl, which was irradiated with X-rays. We observed that the irradiation caused a large spectral weight transfer from the mid-infrared region, where interband transitions in the dimer and Mott-Hubbard bands take place, to a Drude part in a low-energy region; this caused the Mott gap to collapse. The increase of the Drude part indicates a carrier doping into the Mott insulator due to irradiation defects. The strong redistribution of the spectral weight demonstrates that the organic Mott insulator is very close to the phase border of the bandwidth-controlled Mott transition.

4 pages, 4 figures

References in corpus (5)

• Strong electronic correlations in superconducting organic charge transfer salts
• 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
• Quasiparticles at the verge of localization near the Mott metal-insulator transition in a two-dimensional material
• Electronic correlation in the infrared optical properties of the quasi two dimensional $\kappa$-type BEDT-TTF dimer system
• X-ray Irradiation-induced Carrier Doping Effects in Organic Dimer-Mott Insulators

Cited by in corpus (6)

• Electrodynamics of Correlated Electron Materials
• Bandwidth-controlled Mott transition in kappa-(BEDT-TTF)2Cu[N(CN)2]Br{x}Cl{1-x}: Optical studies of correlated carriers
• Electron localization near Mott transition in organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2]$Br
• Shubnikov-de Haas oscillations spectrum of the strongly correlated quasi-2D organic metal (ET)8[Hg4Cl12(C6H5Br)]2 under pressure
• Theory of Electron Transport near Anderson-Mott Transitions
• Metallic Pattern Fabrication in Organic Mott Insulating Crystal by Local X-Ray Irradiation