2026-09-19T15:59:35Zhttps://dspace.mit.edu/server/oai/requestoai:dspace.mit.edu:1721.1/362182022-01-13T07:54:33Zcom_1721.1_7582com_1721.1_7581col_1721.1_131023
Edwin L. Thomas.
Payne, Jeffrey C. (Jeffrey Christopher), 1981-
Massachusetts Institute of Technology. Dept. of Materials Science and Engineering.
Massachusetts Institute of Technology. Department of Materials Science and Engineering
2007-02-21T13:08:47Z
2007-02-21T13:08:47Z
2006
2006
http://hdl.handle.net/1721.1/36218
76906896
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.
Includes bibliographical references (leaves 76-79).
The advancement of the fabrication of a one-dimensional photonic crystal without time-reversal and space-inversion symmetries was pursued. Theoretical studies predict that such a system would exhibit unusual optical properties, including indirect photonic band gaps and backward wave propagating eigenmodes. Such a system can be created experimentally by combing magnetooptical nanoparticles with a chiral nematic liquid crystal. The fabrication of this material system was advanced through two distinct phases of research. The first phase seeks to produce magnetooptical yttrium iron garnet (YIG) nanoparticles with an average diameter on the order of 15-50 nm. It was determined that a commercially available yttrium iron oxide nanopowder (purchased from Sigma-Aldrich Corporation) exhibited YIG and orthorhombic yttrium iron oxide (YFeO3) phases after being calcined at 800 °C for two hours. These nanoparticles were slightly smaller than desired, having diameters on the order of 10-20 nm. Direct nanoparticle synthesis via coprecipitation in microemulsions produced superior results, resulting in a pure YIG material with diameters on the order of 30-50 nm.
(cont.) The second phase examines the manner in which nanoparticles co-assemble with a chiral nematic liquid crystal. It was determined that the addition of nanoparticles to a 5CB-COC system disrupts the system's helical structure. This disruption lowers the system's phase transition temperatures and inhibits the system's ability to form reflectivity peaks.
by Jeffrey Christopher Payne.
S.M.
79 leaves
eng
Massachusetts Institute of Technology
M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.
http://dspace.mit.edu/handle/1721.1/7582
Materials Science and Engineering.
Nanoparticle-chiral nematic liquid crystal composites
Thesis
application/pdf
Publication
unknown
unknown
<Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="1ebab804-8943-46d9-9b30-64ed2928bf8f">
<Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type>
<Language>eng</Language>
<Title>Nanoparticle-chiral nematic liquid crystal composites</Title>
<PublishedIn>
<Publication>
</Publication>
</PublishedIn>
<PublicationDate>2006</PublicationDate>
<Authors>
<Author>
<DisplayName>Payne, Jeffrey C. (Jeffrey Christopher), 1981-</DisplayName>
<Affiliation>
<OrgUnit>
</OrgUnit>
</Affiliation>
</Author>
</Authors>
<Editors>
</Editors>
<Publishers>
<Publisher>
<DisplayName>Massachusetts Institute of Technology</DisplayName>
<OrgUnit />
</Publisher>
</Publishers>
<License>http://dspace.mit.edu/handle/1721.1/7582</License>
<Keyword>Materials Science and Engineering.</Keyword>
<Abstract>The advancement of the fabrication of a one-dimensional photonic crystal without time-reversal and space-inversion symmetries was pursued. Theoretical studies predict that such a system would exhibit unusual optical properties, including indirect photonic band gaps and backward wave propagating eigenmodes. Such a system can be created experimentally by combing magnetooptical nanoparticles with a chiral nematic liquid crystal. The fabrication of this material system was advanced through two distinct phases of research. The first phase seeks to produce magnetooptical yttrium iron garnet (YIG) nanoparticles with an average diameter on the order of 15-50 nm. It was determined that a commercially available yttrium iron oxide nanopowder (purchased from Sigma-Aldrich Corporation) exhibited YIG and orthorhombic yttrium iron oxide (YFeO3) phases after being calcined at 800 °C for two hours. These nanoparticles were slightly smaller than desired, having diameters on the order of 10-20 nm. Direct nanoparticle synthesis via coprecipitation in microemulsions produced superior results, resulting in a pure YIG material with diameters on the order of 30-50 nm.</Abstract>
<Abstract>(cont.) The second phase examines the manner in which nanoparticles co-assemble with a chiral nematic liquid crystal. It was determined that the addition of nanoparticles to a 5CB-COC system disrupts the system's helical structure. This disruption lowers the system's phase transition temperatures and inhibits the system's ability to form reflectivity peaks.</Abstract>
<Access xmlns="http://purl.org/coar/access_right"
>
</Access>
</Publication>