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Journal of Materials Science

, Volume 29, Issue 15, pp 4061–4064 | Cite as

Dielectric properties of quenched and laser-excited or field-treated LiF single crystals irradiated with X-rays

  • P. Selvarajan
  • B. N. Das
  • H. B. Gon
  • K. V. Rao
Papers

Abstract

Frequency and temperature dependences of dielectric constant, K, and loss, tan δ, and hence a.c. conductivity, σ, have been studied for LiF single crystals under a combination of treatments such as quenching, laser excitation, a.c. field treatment and X-ray irradiation. The measurements were made in the frequency range 102–107 Hz and in the temperature range 30–400 °C. The dielectric constant, K, of LiF at 30 °C was found to be 8.4 and to be independent of frequency, while the dielectric loss, tan δ, was below 10−3 at 102 Hz. The results indicate that the different treatments on LiF single crystals increase the room-temperature and also high-temperature K and tan δ values appreciably in the low-frequency region. Log σ versus 1/T plots at frequency 102 Hz give the activation energy for conduction in the intrinsic region as 0.97 eV for as-cleaved LiF; this value was found to decrease in variously treated LiF samples. The different treatments on LiF help to increase the concentration of charged lattice defects which, in turn, increases the K and tan δ values.

Keywords

Polymer Activation Energy Dielectric Constant Dielectric Property Dielectric Loss 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman & Hall 1994

Authors and Affiliations

  • P. Selvarajan
    • 1
  • B. N. Das
    • 1
  • H. B. Gon
    • 1
  • K. V. Rao
    • 1
  1. 1.Department of PhysicsIndian Institute of TechnologyKharagpurIndia

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