Kerr shutters

Kerr Shutter Experiment. The NLO properties of DEANST was also investigated through an optical Kerr shutter experiment. The optical Kerr shutter has the advantages of simple construction and fast response time. DEANST dissolves easily in many solvents. A saturated sample in a DMF (40 wt%) or in a nitrobenzene (30 wt%) was investigated in the Kerr shutter experiment. Powders of DEANST were dissolved in these solvents. The sample solution was poured into a silica glass cell of 1 mm thickness. 

The transmission T value of the Kerr shutter operation was measured and... 

Tlie usual experimental techniques developed to study the optical Kerr effect in materials have already been described in a preceding chapter of this book. We only mention here the methods which have especially been used for nanocomposite materials as colloidal solutions or thin films Degenerate four-wave mixing (DFWM) and optical phase conjugation, which provide the modulus of x only and may be completed by Interferometry techniques to get its phase as well, optical limiting, optical Kerr shutter, and z-scan, which is probably the most common technique used in recent years due to its ability to provide simultaneously the nonlinear refraction and absorption coefficients of the same sample point [118],... 

Microcrystals of some diacetylenes, prepared by the reprecipitation method, have been studied as dispersions in liquid media. Interesting behavior has been observed in the solid-state polymerization of diacetylene monomers and with the optical properties of polydiacetylene (PDA) microcrystals. First, the polymerization perfectly proceeded from one end to the other end of the diacetylene microcrystals. Next, the excitonic absorption peak position was found to shift to higher energy side with decreasing size of the PDA microcrystals. The size effect was observed even for crystals as large as 100 nm or more in contrast to conventional quantum effect of inorganic semiconductors where size effect is observed only for microciystals of less than about 10 nm size. In addition, since the microcrystal dispersions in water have low optical loss, the c tical Kerr shutter response of PDA microciystals could be measured, and the non-resonant value was estimated to be on the order of 10 to 10" esu in very low concentrations (ca. 10 M). 

The Kerr shutter consists of a Kerr cell filled with a liquid, such as nitrobenzene, placed between two crossed polarizers the electric field is arranged to be perpendicular to the axis of the light beam and at 45° to the axis of the polarizers. In the absence of a field there is no optical path through the device. When the field is switched on the nitrobenzene becomes doubly refracting and a path opens between the crossed polarizers. 

Kasai, H., Kanbara, H., lida, R., Okada, S., Matsuda, H., Oikawa, H., and Nakanishi, H., Optical Kerr shutter response of organic microcrystals, Jpn. J. Appl. Phys., 34, L1208, 1995. 

Using powerful polarized light pulses instead of electrical pulses to induce birefringence in traditional Kerr cell liquids, an optical Kerr shutter has been developed with wide ranging applications to picosecond measurements [11.22]. 

The on-olT contrast of the Kerr shutter is a very important parameter which determines the range of emission lifetimes that can be monitored. The residual leakage through the closed gate is integrated by the CCD camera over the entire... 

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