Critical behaviour of the polarization, tilt angle, electric susceptibility and the specific heat close to the SmA-ferroelectric SmC (SmC*) phase transitions

This study gives the temperature dependence of the two order parameters, namely, polarization P and the tilt angle theta, when there is a biquadratic coupling P-2 theta(2) in the expansion of the Landau free energy. This applies to the electric-field-induced SmA-Ferro-Electric SmC (SmC*) phase transition. From this expansion of the Landau free energy in terms of the polarization and the tilt angle, we obtain the temperature dependence of the electric susceptibility chi and the electric field dependence of the polarization P. These dependences of P, theta and chi are fitted to the experimental data for C7 and their critical behaviour in this liquid crystal is described close to the SmA-ferroelectric SmC (SmC*) phase transition.


Temperature dependence of the polarization and tilt angle under an electric field close to the smectic AC* phase transition in a ferroelectric liquid crystal
Yurtseven, Hasan Hamit (Informa UK Limited, 2008-01-01)
The temperature dependence of the polarization P and the tilt angle theta is calculated here in the presence of a constant electric field near the smectic AC* phase transition of a ferroelectric liquid crystal using a mean field model. We demonstrate here the temperature dependence of P and theta under some fixed electric fields for the ferroelectric liquid crystal of 4-(3-methyl-2-chlorobutanoyloxy)-4'-heptyloxybiphenyl. Our predicted values of P and theta at various temperatures under fixed electric field...
Optoelectronic and electrical properties of TlGaS2 single crystal
Qasrawi, AF; Hasanlı, Nızamı (Wiley, 2005-10-01)
The optoelectronic and electrical properties of TIGaS2 single crystals have been investigated by means of room temperature transmittance and reflectance spectral analysis, Hall coefficient, dark electrical resistivity and photocurrent measurements in the temperature range of 200-350 K. The optical data have revealed an indirect and direct allowed transition band gaps of 2.45 and 2.51 eV, an oscillator and dispersion energy of 5.04 and 26.45 eV, respectively, a static dielectric constant of 6.25 and static r...
Nonlinear Seebeck and Peltier effects in quantum point contacts
Çipiloğlu, Mustafa A; Turgut, Sadi; Tomak, Mehmet (Wiley, 2004-09-01)
The charge and entropy currents across a quantum point contact are expanded as a series in powers of the applied bias voltage and the temperature difference. After that, the expansions of the Seebeck voltage in temperature difference and the Peltier heat in current are obtained. With a suitable choice of the average temperature and chemical potential, the lowest order nonlinear term in both cases appear to be of third order. The behavior of the third-order coefficients in both cases are then investigated fo...
Katırcıoğlu, Şenay (Wiley, 1993-06-01)
The stable structures of SinH2m (n = 1 to 6, m = 1 to 3) clusters are investigated by the total electronic energy calculation using an empirical tight-binding (ETB) method. It seems that bridged H-bond models are also possible for small Si(n)H(m) clusters.
Electronic structure of the chainlike compound TlSe
Ellialtıoğlu, Süleyman Şinasi; Mete, E; Shaltaf, R; Allakhverdiev, K; Gashimzade, F; Nizametdinova, M; Orudzhev, G (American Physical Society (APS), 2004-11-01)
An ab initio pseudopotential calculation using density functional theory within the local density approximation has been performed to investigate the electronic properties of TlSe, which is of chainlike crystal geometry. The energy bands and effective masses along high symmetry directions, the density of states, and valence charge density distributions cut through various planes are presented. The results have been discussed in terms of previously existing experimental and theoretical data, and comparisons ...
Citation Formats
H. H. Yurtseven and E. Kilit, “Critical behaviour of the polarization, tilt angle, electric susceptibility and the specific heat close to the SmA-ferroelectric SmC (SmC*) phase transitions,” FERROELECTRICS, pp. 327–336, 2006, Accessed: 00, 2020. [Online]. Available: