Conversion and braiding rules of band-structure nodes
Abstract/Contents
- Abstract
- Topological semimetals are characterized by topologically protected band-structure nodes. One prominent example is the Weyl semimetal, characterized by Weyl points carrying topological Chern numbers. In this dissertation, we explore the topology of band-structure nodes with three ingredients: crystal symmetry, non-Hermiticity and periodic driving. First, we show that point group symmetry facilitates a new type of topological invariant from relative homotopy theory, which determines the rules for converting generic band nodes to nodes at high-symmetry momenta (and vice versa) as we tune the lattice Hamiltonian. Secondly, we show that exceptional lines in non-Hermitian bands act as Alice strings. This is manifested by the reversal of the topological charge of a node, if it is braided around an exceptional line. Finally, we discuss the Nielsen-Ninomiya no-go theorem in Floquet bands and the possibility of simulating chiral Weyl particles in the adiabatic limit
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2020; ©2020 |
| Publication date | 2020; 2020 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Sun, Xiaoqi, active 2020 |
|---|---|
| Degree supervisor | Qi, Xiaoliang |
| Thesis advisor | Qi, Xiaoliang |
| Thesis advisor | Fan, Shanhui, 1972- |
| Thesis advisor | Kivelson, Steven |
| Degree committee member | Fan, Shanhui, 1972- |
| Degree committee member | Kivelson, Steven |
| Associated with | Stanford University, Department of Physics. |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Xiaoqi Sun |
|---|---|
| Note | Submitted to the Department of Physics |
| Thesis | Thesis Ph.D. Stanford University 2020 |
| Location | electronic resource |
Access conditions
- Copyright
- © 2020 by Xiaoqi Sun
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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