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Pablo Jarillo-Herrero. Cao, Yuan, Ph. D. Massachusetts Institute of Technology Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science 2016-12-05T19:57:59Z 2016-12-05T19:57:59Z 2016 2016 http://hdl.handle.net/1721.1/105685 964450770 Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016. Cataloged from PDF version of thesis. Includes bibliographical references (pages 47-48). Graphene is a two-dimensional material with exotic electronic, optical and mechanical properties. By stacking two layers of graphene together with a small rotation angle between them, a superlattice of arbitrarily large size can be formed. The hybridization of the electronic states in the two layers can result in reduced Fermi velocity, van Hove singularities and a gapped band structure. In this work, a novel tear-and-stack technique is developed to reliably produce twisted bilayer graphene with controlled angle, and electronic transport measurements of the resulting high-quality samples are performed and discussed. We discover novel insulating states that purely results from the moiŕe superlattice band structure. The magnetotransport properties of these insulating states are studied and indicate that these states have different structure with those in either graphene or AB-stacked bilayer graphene; it shows a non-monotonous change of Fermi surface area which agrees with theoretical calculations. The results point toward a new pathway for graphene-related physics and material research. by Yuan Cao. S.M. 48 pages 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 Electrical Engineering and Computer Science. Electronic transport in low-angle twisted bilayer graphene Thesis application/pdf Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="b202e05e-51c5-4469-a00c-a714283b52c7"> <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>Electronic transport in low-angle twisted bilayer graphene</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2016</PublicationDate> <Authors> <Author> <DisplayName>Cao, Yuan, Ph. D. Massachusetts Institute of Technology</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>Electrical Engineering and Computer Science.</Keyword> <Abstract>Graphene is a two-dimensional material with exotic electronic, optical and mechanical properties. By stacking two layers of graphene together with a small rotation angle between them, a superlattice of arbitrarily large size can be formed. The hybridization of the electronic states in the two layers can result in reduced Fermi velocity, van Hove singularities and a gapped band structure. In this work, a novel tear-and-stack technique is developed to reliably produce twisted bilayer graphene with controlled angle, and electronic transport measurements of the resulting high-quality samples are performed and discussed. We discover novel insulating states that purely results from the moiŕe superlattice band structure. The magnetotransport properties of these insulating states are studied and indicate that these states have different structure with those in either graphene or AB-stacked bilayer graphene; it shows a non-monotonous change of Fermi surface area which agrees with theoretical calculations. The results point toward a new pathway for graphene-related physics and material research.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>