Probing the Electric-Field Modulated Ferroelectric Liquid Crystal Films with Phase-Sensitive Raman Imaging Technique

The electric-field-induced modulation of surface stabilized ferroelectric liquid crystal (SSFLC) films was investigated with a phase sensitive Raman imaging. We found the technique not only effectively suppresses the nonresonant background of a Raman spectrum, but also yields an insight into the modulated amplitudes and phases of Raman peaks. By using the technique, the electro-optical switching SSFLC film doped with ZnO nanocrystals (nc-ZnO) was shown to switch in a more organized way and be less sensitive to the modulation induced disordering than an undoped SSFLC film. The method can be implemented in a conventional Raman spectroscopy to allow researchers probing into the spatial distribution and modulation dynamics of electro-optic active species in a complex thin film. PACS: 300.6450; 180.0180; 160.3710; 170.4090.