学术报告

报告题目:Electric-field control of optical activity of polymer-stabilized blue phase layers

报告人:    Prof. Dr. Andrey Iljin

Institute of Physics

National Academy of Sciences of Ukraine,

Kiev, Ukraine

时间：     11月19日10:00 （周二）

地点：     泰达应用物理研究院四楼报告厅

Since 2002, when Kikuchi et al. reported of a huge expansion of the temperature range of blue phase existence due to introduction of a small amount of polymers, it has attracted a lot of interest. In such a system, referred to as “polymer-stabilized blue phases” (PSBPh), molecular arrangement retains a double-twisted helical structure and exhibits a very fast electro-optical response to applied electric field in the plane of substrates. Being comprised of chiral nano-domains PSBPh reveals quite substantial optical activity, which is weakened under the on-axis electric field application due to distortion of their twisted molecular structure.

Electric field influence on optical activity of PSBPh cells is studied. Efficient electro-optic change of light wave polarization possesses a rate-dependent type of hysteresis with a simple phase lag between the input and output for comparatively low voltages (< 100 V): where V is the voltage of frequency ω applied, T is the cell transmission in crossed polarizers. Times characteristic of elastic deformations appearing for voltages below 100 V, are of the order of ms. Further increase of the voltage reveals transition of response behavior to saturation and slow viscous inelastic deformations.

Control of light polarization orientation via the electro-optic modulation of optical activity of PSBPh might be useful for optical wave polarization patterning, creation of complex vectorial field profiles or in some multichannel optical information processing systems.

邀请人:    张心正  教授

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