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dc.contributor.authorLillianfeld, Robert Brianen_US
dc.date.accessioned2014-03-14T20:09:42Z
dc.date.available2014-03-14T20:09:42Z
dc.date.issued2011-04-01en_US
dc.identifier.otheretd-04152011-115313en_US
dc.identifier.urihttp://hdl.handle.net/10919/26889
dc.description.abstractWe have studied the electron quantum phase by fabricating low dimensional (d â ¤ 2) mesoscopic interferometers in high-quality narrow-gap semiconductor (NGS) heterostructures. The low effective-mass electrons in NGS heterostructures enable observation of delicate quantum phases; and the strong spin-orbit interaction (SOI) in the systems gives us means by which we can manipulate the quantum-mechanical spin of these electrons through the orbital properties of the electrons. This enables the observation of spin-dependent phenomena otherwise inaccessible in non-magnetic systems. We have performed low temperature (0.4 K â ¤ T â ¤ 8 K), low noise (â V ~ 1μV ) transport measurements, and observed evidence of Aharonov-Bohm (AB) and Alâ tshuler-Aronov-Spivak (AAS) quantum oscillations in meso- scopic devices that we fabricated on these NGSs. Our measurements are unique in that we observe both AB and AAS in comparable magnitude in ballistic networks with strong SOI. We show that, with appropriate considerations, diffusive formalisms can be used to describe ballistic transport through rings, even in the presence of SOI. This work also contains an introduction to the physics of geometric phases in mesoscopic systems, and the experimental and analytic processes through which these phases are probed. A discussion of the results of our measurements presents the case that quantum interferometric measurements of geometric phases can be understood quite thoroughly, and that these measurements may have deeper utility in discovery than has yet been recognized.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartLillianfeld_RB_D_2011_Copyright.pdfen_US
dc.relation.haspartLillianfeld_RB_D_2011.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectquantum interferenceen_US
dc.subjectmesoscopic physicsen_US
dc.subjectAharonov-Bohm effecten_US
dc.subjectdephasingen_US
dc.titleExperimental Observation of Geometric Phases in Narrow-Gap Semiconductor Heterostructuresen_US
dc.typeDissertationen_US
dc.contributor.departmentPhysicsen_US
dc.description.degreePh. D.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplinePhysicsen_US
dc.contributor.committeechairHeremans, Jean Josephen_US
dc.contributor.committeememberAsryan, Levon V.en_US
dc.contributor.committeememberHeflin, James R.en_US
dc.contributor.committeememberKulkarni, Rahul V.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-04152011-115313/en_US
dc.date.sdate2011-04-15en_US
dc.date.rdate2011-05-03
dc.date.adate2011-05-03en_US


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