Understanding, constructing, and probing highly-entangled phases of quantum matter

In this thesis, I explore three classes of quantum phases of matter that cannot be understood purely on the basis of symmetry, and can be regarded (to varying degrees) as having highly-entangled ground-states. The first Part describes topological superconductors with non-Abelian defects, and develops realistic routes to constructing these exotic superconductors from more elementary materials. Particular attention is payed to practical issues such as disorder. The second Part examines the role of interactions in electron topological insulators (TIs). Non-perturbative definitions of the familiar topological band-insulator are given, and new strongly-correlated TIs with no band-structure analogs are identified. The last Part turns exotic gapless phases without quasi-particle excitations, focusing on topics related to recently discovered quantum spin-liquid (QSL) materials. The possibility of a gapless QSL in the vicinity of the metal-insulator transition in doped semiconductors is explored, and optical conductivity is developed as an experimental tool to examine the nature of the QSL candidate Herbertsmithite. The material of this thesis is closely parallels that of Refs [1, 2, 3, 4, 5, 7,8, 9,10, 11].

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2013

Author dc:creator

• Potter, Andrew C. (Andrew Cole)

Advisor dc:contributor.advisor

• Patrick A. Lee.

• Physics.

Statement dc:rights

• 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.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/84392

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/84392