The Goldstone mode in ferroelectric liquid crystals A non-linear dielectric loss process

Abstract The dielectrically observed Goldstone mode in ferroelectric liquid crystals is shown to have, beside the well-known DC bias field dependence, a strong AC field dependence of the dielectric loss. This non-linearity arises at AC field strengths > 100 V/cm already in the materials which we have studied. It is maximal at the frequency of maximum loss of the Goldstone mode and levels off at frequencies far enough apart. Thus attempts to analyse the Goldstone mode within the framework of the linear response theory are not applicable in general, but are restricted to sufficiently small AC fields.

[1]  D. D. Yue,et al.  Theory of Electric Polarization , 1974 .

[2]  P. Martinot-Lagarde,et al.  Dielectric relaxation in a ferroelectric liquid crystal , 1981 .

[3]  E. Rietman,et al.  Audio frequency dielectric response of the liquid-crystal ce8 in chiral and racemic forms , 1986 .

[4]  M. Ozaki,et al.  New Ferroelectric Liquid Crystals with Spontaneous Polarization Exceeding 10−7C/cm2 and Their Electrical and Optical Properties , 1987 .

[5]  Carlsson,et al.  Goldstone mode and soft mode at the smectic-A-smectic-C phase transition studied by dielectric relaxation. , 1987, Physical review. A, General physics.

[6]  Patel,et al.  Thin-cell dielectric response of a ferroelectric liquid crystal. , 1987, Physical review. A, General physics.

[7]  Carlsson,et al.  Dielectric properties near the smectic-C-smectic-A phase transition of some ferroelectric liquid-crystalline systems with a very large spontaneous polarization. , 1988, Physical review. A, General physics.

[8]  Haase,et al.  Dielectric relaxation in the smectic-A and smectic-C phases of a ferroelectric liquid crystal. , 1989, Physical review. A, General physics.

[9]  F. Kremer,et al.  Broadband dielectric spectroscopy on the molecular dynamics in polymer model-systems: polyphenylmethylsiloxane and linear and star-branched poly(cis-1,4-isoprene) , 1989 .

[10]  M. Glogarová,et al.  The effect of biasing electric field on the soft mode in the vicinity of the ferroelectric phase transition in liquid crystals , 1989 .

[11]  F. Kremer,et al.  Field dependent soft and goldstone mode in a ferroelectric liquid crystal as studied by dielectric spectroscopy , 1989 .

[12]  F. Kremer,et al.  Ferroelectric modes in combined side-group main chain liquid-crystalline polymers , 1989 .

[13]  S. Lagerwall,et al.  Experimental and theoretical study of the influence of a bias electric field on the dielectric properties of the chiral smectic A* phase , 1989 .

[14]  M. Ozaki,et al.  The characteristic dielectric behaviour in ferroelectric liquid crystals at a phase transition and the contribution of the soft mode , 1989 .

[15]  W. Haase,et al.  Dielectric studies of a ferroelectric liquid crystal , 1989 .

[16]  F. Kremer,et al.  A molecular gyroscope based on the goldstone mode in ferroelectric liquid crystals , 1990 .

[17]  F. Kremer,et al.  Broadband dielectric spectroscopy on ferroelectric liquid-crystalline side group polymers , 1990 .

[18]  F. Kremer,et al.  Softmode at the ferroelectric/non ferroelectric phase-transition in a liquid crystalline polymer , 1990 .