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Author ORCID Identifier
https://orcid.org/0000-0001-6781-981X
AccessType
Open Access Dissertation
Document Type
dissertation
Degree Name
Doctor of Philosophy (PhD)
Degree Program
Physics
Year Degree Awarded
2022
Month Degree Awarded
September
First Advisor
Tigran Sedrakyan
Second Advisor
Nikolay Prokof’ev
Third Advisor
Boris Svistunov
Fourth Advisor
Owen Gwilliam
Subject Categories
Condensed Matter Physics | Quantum Physics | Statistical, Nonlinear, and Soft Matter Physics
Abstract
Quantum criticality in low-dimensional quantum systems is known to host exotic behaviors. In quantum one-dimension (1D), the emerging conformal group contains infinite generators, and conformal techniques, e.g., operator product expansion, give accurate and universal descriptions of underlying systems. In quantum two-dimension (2D), the electronic interaction causes singular corrections to Fermi-liquids characteristics. Meanwhile, the Dirac fermions in topological 2D materials can greatly enrich emerging phenomena. In this thesis, we study the symmetry-breaking effects of low-dimensional quantum criticality. In 1D, we consider two cases: time-reversal symmetry (TRS) breaking in the Majorana conformal field theory (CFT) and the absence of conformal symmetry in the $z=2$ Lifshitz criticality. In both cases, universal features of quantum criticality exhibit exotic behaviors, e.g., the finite-size amplitude and entanglement entropy. In 2D, we study the effect of a weak perpendicular magnetic field on the doped graphene. We establish the chiral symmetry breaking mechanism induced by the field and explore its many-body consequences, e.g., thermodynamics and magnetoresistance.
DOI
https://doi.org/10.7275/30712401
Recommended Citation
Wang, Ke, "Symmetry Breaking Effects in Low-Dimensional Quantum Systems" (2022). Doctoral Dissertations. 2688.
https://doi.org/10.7275/30712401
https://scholarworks.umass.edu/dissertations_2/2688
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Included in
Condensed Matter Physics Commons, Quantum Physics Commons, Statistical, Nonlinear, and Soft Matter Physics Commons