Non-linear dielectric spectra of ferroelectric liquid crystals

Yasuyuki Kimura, Reinosuke Hayakawa

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The non-linear dielectric relaxation spectroscopy has been recently developed and applied to soft materials such as polymers. We have applied this new method to the S*C phases of some ferroelectric liquid crystals. Under a weak AC electric field, the original and third order harmonic frequency components of electric displacement are proportional to the first and third powers of the applied electric field, respectively. The linear spectrum obtained from the original frequency component shows the relaxation of Debye type and the third order non-linear spectrum shows the relaxation with an extended form of Debye type to the non-linear case. The third order non-linear dielectric increment is found to be negative, which implies that the dielectric non-linearity of the liquid crystal in the S*C phase is due to the saturation of molecular dipole moments induced by the applied electric field. The temperature dependence of the linear and third order non-linear spectra in the S*C phase are also studied. Both spectra do not change their forms much through the whole temperature range of the S*C phase. In the vicinity of the SA–S*C transition temperature, the critical behaviour is more remarkable in the third order spectrum than in the linear one.

Original languageEnglish
Pages (from-to)427-434
Number of pages8
JournalLiquid Crystals
Volume14
Issue number2
DOIs
Publication statusPublished - Jan 1 1993
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Non-linear dielectric spectra of ferroelectric liquid crystals'. Together they form a unique fingerprint.

  • Cite this