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

Published online by Cambridge University Press:  10 February 2011

Daniel J. Dyer
Affiliation:
Department of Chemistry and Biochemistry
Renfan Shao
Affiliation:
Department of Physics, and Optoelectronic Computer System Center, University of Colorado, Boulder CO 80309-0215
Noel A. Clark
Affiliation:
Department of Physics, and Optoelectronic Computer System Center, University of Colorado, Boulder CO 80309-0215
David M. Walba
Affiliation:
Department of Chemistry and Biochemistry
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Abstract

With 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.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

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References

REFERENCES

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