Design and synthesis of ferroelectric liquid crystals. 24. Incorporation of the disperse red 1 chromophqre into side-by-side dimers for nonlinear optics

1995 ◽  
Vol 413 ◽  
Author(s):  
Daniel J. Dyer ◽  
Renfan Shao ◽  
Noel A. Clark ◽  
David M. Walba

ABSTRACTWith excellent processibility on silicon integrated circuits and thermodynamically stable polar order, ferroelectric liquid crystals (FLCs) show great potential as components of fast integrated electro-optic modulators. In order to realize this potential, however, an increase in the magnitude of the electronic secona order nonlinear susceptibility χ(2) is required. This has been problematical since functional arrays with large molecular second order susceptibility β orient with improper supermolecular stereocontrol (i.e. with the charge transfer axis normal to the polar axis) when incorporated into traditional FLC structures. Herein we present examples of a new LC structural class designed to achieve the proper supermolecular structure for large χ(2) in FLCs. The observed sign and magnitude of the ferroelectric polarization of the new mesogens extrapolated from smectic C* mixtures is fully consistent with the desired supermolecular structure.

1995 ◽  
Vol 392 ◽  
Author(s):  
Kenneth E. Arnett ◽  
David M. Walba ◽  
Joel A. Drewes

AbstractAmong soft organic nonlinear optical materials is a class of recently developed: χ(2)_ enhanced ferroelectric liquid crystals (FLCs). The FLC phase nonlinear susceptibility is enhanced by synthesizing onto the molecules constituting the FLC phase a moiety with an increased hyperpolarizability. The hyperpolarizability of the FLC molecules couples into the permanent, thermodynamically stable, polar order of the FLC phase resulting in a material with an enhanced nonlinear susceptibility. Like other soft organics, the linear and nonlinear optical materials characteristics can be altered by chemical synthesis and mixing.We report on our technique to evaluate the nonlinear optical properties of χ(2)-enhanced FLCs by measuring their high-frequency electro-optic r-coefficients. The technique is broad-band, readily allowing electro-optic coefficient measurement between 100 KHz and 200 MHz. Although the experimental geometry is not conducive for practical device application, it offers a compromise between ease of fabrication and magnitude of nonlinear response. This technique can also be used to evaluate other organic materials such as poled polymers.


1994 ◽  
Vol 72 (22) ◽  
pp. 3558-3561 ◽  
Author(s):  
Shankar B. Rananavare ◽  
V. G. K. M. Pisipati ◽  
E. W. Wong

2007 ◽  
Vol 399 (1) ◽  
pp. 60-65 ◽  
Author(s):  
J. Hemine ◽  
A. Daoudi ◽  
C. Legrand ◽  
N. Isaert ◽  
A. El kaaouachi ◽  
...  

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