TIME-SCALE DEPENDENCE OF THE CRITICAL EXPONENT FOR THE NONLINEAR DIELECTRIC EFFECT IN A CRITICAL BINARY-SOLUTION

Low frequency [(300 kHz) results for the nonlinear dielectric effect ( NDE)] (variation in electric permittivity of liquids induced by a stro ng, steady electric field) in a critical, binary solution have been ob tained. Their comparison with NDE measurements for 9 and 6 MHz indicat e that the appearance of a mean-field region near the critical consolu te temperature (T-c) and the crossover to the nonclassical behavior re mote from T-c could be associated not only with the degree of elongati on of critical fluctuations but also with the time scale involved. Thi s behavior is possibly due to the correlation between the relaxation t ime of critical fluctuations and the measurement frequency. The result obtained supplements the analysis given in Phys. Rev. E 48, 1136 (199 3) plus Phys. Rev. E 47, 1445 (1993) and Phys. Rev. E 50, 5234 (1994) of the behavior near a critical consolute point of two effects immanen tly associated with the application of a strong, steady electric field : the electro-optical Kerr effect and nonlinear dielectric effect.