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dc.contributor.advisorMildred S. Dresselhaus.en_US
dc.contributor.authorLevin, Andrei Jen_US
dc.contributor.otherMassachusetts Institute of Technology. Dept. of Physics.en_US
dc.date.accessioned2009-03-16T19:39:40Z
dc.date.available2009-03-16T19:39:40Z
dc.date.copyright2008en_US
dc.date.issued2008en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/44760
dc.descriptionThesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2008.en_US
dc.descriptionIncludes bibliographical references (leaves 61-62).en_US
dc.description.abstractDue to the unique electronic properties of bismuth, bismuth nanowires provide an attractive low-dimensional system for studying quantum confinement effects, and have generated much interest in both optical and thermoelectric applications. Two especially interesting features of bismuth nanowires are the non-parabolic nature of the electronic energy bands near the Fermi level and the large anisotropy of the carrier pockets. As a result of these features, the electronic properties of bismuth nanowires depend strongly on both crystalline orientation and nanowire diameter. In order to study the effect of crystalline orientation, we first derive a simple method to transform from hexagonal to Cartesian coordinates in the bismuth lattice. We then investigate an important indirect electronic transition in bismuth nanowires, and we use the Lax two-band model to develop a theoretical model for studying the diameter dependence of the energy of this transition for nanowires of any crystalline orientation. Our theoretical model shows good agreement with previous experimental results, and demonstrates that the parabolic approximation of the non-parabolic electronic energy bands is inappropriate. Finally, we perform room-temperature IR spectroscopy measurements, in both the reflection and transmission modes, on three sets of bismuth nanowire samples of different crystalline orientation, each fabricated by a different research group. Our results confirm that the notable differences in the measured electronic spectra of the three sets of samples are physical in nature, and are not due to differences in the experimental setups.en_US
dc.description.statementofresponsibilityby Andrei J. Levin.en_US
dc.format.extent62 leavesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.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.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectPhysics.en_US
dc.titleThe effect of crystalline orientation and band non-parabolicity on the electronic properties of bismuth nanowiresen_US
dc.typeThesisen_US
dc.description.degreeS.B.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Dept. of Physics.en_US
dc.identifier.oclc299069647en_US


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