Hostname: page-component-8448b6f56d-t5pn6 Total loading time: 0 Render date: 2024-04-24T07:21:51.128Z Has data issue: false hasContentIssue false

Interactions Between Carbon Nanotubes and Liquid Crystals in Binary Nematic Electro-Optic Cells

Published online by Cambridge University Press:  31 January 2011

Georgi Yordanov Georgiev
Affiliation:
georgi@alumni.tufts.eduggeorgie@assumption.edu, Assumption College, Natural Science, 500 Salisbury st, 104 Testa Center, Worcester, Massachusetts, 01609, United States, 6175087251
Erin A Gombos
Affiliation:
ggeorgie@assumption.edu, Assumption College, Natural Science, Worcester, Massachusetts, United States
Michael B McIntyre
Affiliation:
mmcintyre@assumption.edu, Assumption College, Natural Science, Worcester, Massachusetts, United States
Michael F Mattera
Affiliation:
mmatera@assumption.edu, Assumption College, Natural Science, Worcester, Massachusetts, United States
Peter A. Gati
Affiliation:
pgati@assumption.edu, Assumption College, Natural Science, Worcester, Massachusetts, United States
Yaniel Cabrera
Affiliation:
ycabrera@tufts.edu, Tufts University, Physics and Astronomy, Medford, Massachusetts, United States
Peggy Cebe
Affiliation:
peggy.cebe@tufts.edu, United States
Get access

Abstract

We studied the effects of multiwalled carbon nanotubes (MWCNTs) on the Freedericksz transition of a liquid crystal (LC) and calibrated the altitudinal angle of CNTs as a function of the electric field. In addition, we directed the azimuthal angle which gave us complete control of the 3D orientation of the CNTs. We constructed anti-parallel electro-optic cells using a nanocomposite at a concentration of 0.01% CNTs with 4-Cyano-4'-pentylbiphenyl (5CB) liquid crystal. This low concentration was necessary to achieve maximum transmission of electromagnetic radiation through the cell and to minimize the Van der Waals attraction between the CNTs responsible for their aggregation. We chose two dimensional microscopic transmission ellipsometry (2D-MTE) to measure the phaseshift of the polarized electromagnetic radiation through the cell and to derive from it the altitudinal angle of the CNTs. Our results show that in the presence of CNTs the Freedericksz transition occurs at 55% of the transitional electric field as compared to the control electro-optic cell without CNTs. The width of the Freedericksz transition narrows by a similar factor. The switching time of the cell decreased in the presence CNTs by 18.5%.

Type
Research Article
Copyright
Copyright © Materials Research Society 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 Song, W. Kinloch, I.A. Windle, A.H. Science 302, 1363 (2003).Google Scholar
2 Fray, D. Langhorst, B. Kim, H. Grulke, E. Wang, H. Hobbie, E.K. Phys. Rev. Lett. 95, 038304 (2005).Google Scholar
3 Islam, M.F. Alsayed, A.M. Dogic, Z. Zhang, J. Lubensky, T.C. Yodh, A.G. Phys. Rev. Lett. 92, 088303 (2004).Google Scholar
4 Lynch, M.D. Patrick, D.L. Nano Lett. 2, 11 (2002).Google Scholar
5 Dierking, I. Scalia, G. Morales, P. J. Appl. Phys. 92, 8 (2004).Google Scholar
6 Lee, W. Wang, C. Shih, Y.. Appl. Phys. Lett. 85, 4 (2004).Google Scholar
7 Rahman, M. Lee, W. J. Phys. Appl. Phys. 42, 063001 (2009).Google Scholar
8 Blake, G.I. Mullin, T. Tavener, S.J. Dynam. Stabil. Syst. 14, 3 (1999).Google Scholar
9 Georgiev, G. Ph.D. Thesis, Tufts University, 2002.Google Scholar
10 Chen, H. and Lee, W. Appl. Phys. Lett. 88, 222105 (2006)Google Scholar