Journal of Materials Science

, Volume 16, Issue 3, pp 775–779 | Cite as

On electrical transport in CoWO4 single crystals

  • R. Bharati
  • R. A. Singh
  • B. M. Wanklyn
Papers

Abstract

CoWO4 is a p-type semiconductor with conductivity in the range 10−8 to 10−3 ohm−1 cm−1. The solid exhibits extrinsic behaviour up to 750 K and intrinsic behaviour above 750 K. In this solid conduction by hopping of small polarons seems to be dominating up to 750 K and above 750 K conduction becomes band type. The energy band gap of the solid has been found to be 2.80 eV. The values of mobility and the mean free path are estimated. The variation of dielectric constant with temperature has been attributed to changes in atomic and ionic polarization and space charge polarization of thermally generated charge carriers.

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Copyright information

© Chapman and Hall Ltd 1981

Authors and Affiliations

  • R. Bharati
    • 1
  • R. A. Singh
    • 1
  • B. M. Wanklyn
    • 2
  1. 1.Department of PhysicsUniversity of GorakhpurGorakhpurIndia
  2. 2.Department of PhysicsUniversity of Oxford, Clarendon LaboratoryOxfordUK

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