Optical conductivity of V4O7 across its metal-insulator transition

Abstract

The optical properties of a V4O7 single crystal have been investigated from the high temperature metallic phase down to the low temperature antiferromagnetic insulating one. The temperature dependent behavior of the optical conductivity across the metal-insulator transition (MIT) can be explained in a polaronic scenario. Charge carriers form strongly localized polarons in the insulating phase as suggested by a far-infrared charge gap abruptly opening at T_MIT = 237 K. In the metallic phase instead the presence of a Drude term is indicative of fairly delocalized charges with a moderately renormalized mass m* = 5m_e. The electronic spectral weight is almost recovered on an energy scale of 1 eV, which is much narrower compared to VO2 and V2O3 cases. Those findings suggest that electron-lattice interaction rather than electronic correlation is the driving force for V4O7 metal-insulator transition.

arXiv comment5 pages, 3 figures

References in corpus (14)

• Froehlich Polaron and Bipolaron: Recent Developments
• Infrared and Raman studies of the Verwey transition in magnetite
• Electrodynamics of the vanadium oxides VO2 and V2O3
• Electron-phonon interaction and charge carrier mass enhancement in SrTiO3
• A Microscopic View on the Mott transition in Chromium-doped V2O3
• The vanadium Magneli phases VnO(2n-1)
• Quasiparticle evolution and pseudogap formation in V2O3: An infrared spectroscopy study
• Fano effect in the $a-b$ plane of Nd${}_{1.96}$Ce${}_{0.04}$CuO${}_{4+y}$: evidence of phonon interaction with a polaronic background
• The Charge Ordered State from Weak to Strong Coupling
• Electrodynamics near the Metal-to-Insulator Transition in V3O5
• From VO2 to V2O3: The Metal-Insulator Transition of the Magneli Phase V6O11
• Optical Properties of (SrMnO3)n/(LaMnO3)2n superlattices: an insulator-to-metal transition observed in the absence of disorder
• The Metal-Insulator Transition of the Magneli phase V_4O_7: Implications for V_2O_3
• Electronic structure of V${}_4$O${}_7$: charge ordering, metal-insulator transition and magnetism

Cited by in corpus (1)

• Optical properties of V2O3 in its whole phase diagram