Electric-field-dependent dielectric response in the de Vries-type smectic- A phase possessing local orientational order with nanoscale correlation length.
The dielectric strength is shown to increase and the relaxation frequency to decrease for a large temperature range up to a certain value of the electric field in the smectic- A phase. This behavior contrasts to that observed in a conventional smectic- A , but can be explained in terms of de Vries scenerio. On assuming the reorientation of the molecular dipoles with electric field to be of the Langevin type in the de Vries smectic- A, we find that around 1,300 molecules , corresponding to a minimum correlation length of xi_{ perpendicular} approximately 45 nm in a single layer cooperatively respond to the applied field.
Manna
U
U
Department of Electronic and Electrical Engineering, Trinity College, University of Dublin, Dublin 2, Ireland.
Song
Jang-Kun
JK
Vij
J K
JK
Naciri
J
J