The mechanism of polymer alignment of liquid-crystal materialsJ. Geary, J. W. Goodby, A. R. Kmetz et al.|Journal of Applied Physics|1987 Smetic and nematic liquid-crystal materials can be homogeneously aligned by buffed thin films of appropriate polymers. We propose that the buffing process orients the polymer’s molecular chains in a manner similar to cold drawing of bulk polymer samples. Experimental verification of this theory is obtained by measuring buffing-induced birefringence in thin films of various polymers coated on glass. Further experiments establish that the oriented state of the polymer chains, and not scratching or grooving of the surface, is necessary to produce alignment. Alignment is found to occur when the polymer is both oriented and crystalline. A picture of alignment is presented in which the formation of a liquid-crystal phase on the crystalline,oriented polymer surface is analogous to the epitaxial growth of conventional solid crystals.
Helical twist sense and spontaneous polarization direction in ferroelectric smectic liquid crystals. 1John W. Goodby, E. Chin, Thomas M. Leslie et al.|Journal of the American Chemical Society|1986 ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHelical twist sense and spontaneous polarization direction in ferroelectric smectic liquid crystals. 1J. W. Goodby, E. Chin, T. M. Leslie, J. M. Geary, and J. S. PatelCite this: J. Am. Chem. Soc. 1986, 108, 16, 4729–4735Publication Date (Print):August 1, 1986Publication History Published online1 May 2002Published inissue 1 August 1986https://pubs.acs.org/doi/10.1021/ja00276a008https://doi.org/10.1021/ja00276a008research-articleACS PublicationsRequest reuse permissionsArticle Views346Altmetric-Citations101LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
40-Gb/s tandem electroabsorption modulatorB. Mason, A. Ougazzaden, C.W. Lentz et al.|IEEE Photonics Technology Letters|2002 In this letter, we have developed a tandem electroabsorption modulator with an integrated semiconductor optical amplifier that is capable of both nonreturn-to-zero and return-to-zero (RZ) data transmission at 40 Gb/s. The tandem modulator consists of a broad-band data encoder and a narrow-band pulse carver. The pulse carver is able to produce 5-ps pulses with more than 20 dB of extinction. The on-chip semiconductor optical amplifier provides up to 8.5 dB of fiber-to-fiber gain and enables the modulator to be operated with zero insertion loss. Devices have been realized with greater than 40-GHz bandwidth, and 13-dB dynamic extinction for a 2.5-V swing. For optimized designs bandwidths of nearly 60 GHz: have been realized. Using these devices penalty free RZ data transmission over a 100-kin dispersion compensated fiber link has been demonstrated with a received power sensitivity of -29 dBm.