Metal-insulator transition in highly conducting oriented polymers
نویسنده
چکیده
We suggest that highly conducting oriented polymers with a fibril structure can be modeled by a regular lattice of disordered metallic wires with a random first-neighbor interwire coupling which mimics the cross-links between fibrils. We show that such a model can be described by a non-linear sigma model. Within a one-loop self-consistent approximation, we determine the position of the metal-insulator transition as a function of interwire cross-links concentration, interwire coupling and number of polymer chains in a wire. PACS numbers: 71.20Hk, 71.30.+h, 72.15.Rn Typeset using REVTEX
منابع مشابه
Terahertz spectroscopy studies on epitaxial vanadium dioxide thin films across the metal-insulator transition.
We present results on terahertz (THz) spectroscopy on epitaxial vanadium dioxide (VO(2)) films grown on sapphire across the metal-insulator transition. X-ray diffraction indicates the VO(2) film is highly oriented with the crystallographic relationship: (002)(film)//(0006)(sub) and [010](film)//[2 ̅1 ̅10](sub). THz studies measuring the change in transmission as a function of temperature demonstr...
متن کاملMacroscopic disorder and the metal–insulator transition in conducting polymers
We describe a simple model for treating the frequency-dependent conductivity σe(ω) and dielectric function Re e(ω) of a quasi-one-dimensional conducting polymer. The polymer is modelled as a composite medium consisting of spherical regions of ordered polymer, randomly distributed in a much more disordered polymer host. Within each spherical region, the polymer chains are highly oriented, but th...
متن کاملMetal-insulator Transition (scaling Theory)
In this paper I brieey discuss the concepts of localization and metal-insulator transition. The phenomenological description of the conducting properties depending on the dimensionality and disorder, and the physical arguments for the scaling-function are presented. The conducting properties of the 3D system near the critical point of the metal-insulator transition predicted by this scaling mod...
متن کاملSynthesis of vanadium dioxide thin films on conducting oxides and metal–insulator transition characteristics
We report on growth and physical properties of vanadium dioxide (VO2) films on model conducting oxide underlayers (Nb-doped SrTiO3 and RuO2 buffered TiO2 single crystals). The VO2 films, synthesized by rf sputtering, are highly textured as seen from X-ray diffraction. The VO2 film grown on Nb doped SrTiO3 shows over two orders of magnitude metal–insulator transition, while VO2 film on RuO2 buff...
متن کاملMetal-insulator transition in C60 polymers.
Variations in the band structures of C60-polymers are studied, when π-conjugation conditions are changed. We look at band structures in order to discuss a metal-insulator transition, using a semi-empirical model with the Su-SchriefferHeeger type electron-phonon interactions. We find that electronic structures change among direct-gap insulators and the metal, depending on the degree of π-conjuga...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2008