### Gapped boundary phases of topological insulators via weak coupling

The standard boundary state of a topological insulator in 3 + 1 dimensions has gapless charged fermions. We present model systems that reproduce this standard gapless boundary state in one phase, but also have gapped phases with topological order. Our models are weakly coupled and all the dynamics is explicit. We rederive some known boundary states of topological insulators and construct new ones. Consistency with the standard spin/charge relation of condensed matter physics places a nontrivial constraint on models

- Publication Date:

- Grant/Contract Number:
- sc0009988

- Type:
- Accepted Manuscript

- Journal Name:
- Progress of Theoretical and Experimental Physics

- Additional Journal Information:
- Journal Volume: 2016; Journal Issue: 12; Journal ID: ISSN 2050-3911

- Publisher:
- Physical Society of Japan

- Research Org:
- Inst. for Advanced Study, Princeton, NJ (United States)

- Sponsoring Org:
- USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Quantization and formalism; Symmetries and anomalies; Vortices; Other topics

- OSTI Identifier:
- 1424001

```
Seiberg, Nathan, and Witten, Edward.
```*Gapped boundary phases of topological insulators via weak coupling*. United States: N. p.,
Web. doi:10.1093/ptep/ptw083.

```
Seiberg, Nathan, & Witten, Edward.
```*Gapped boundary phases of topological insulators via weak coupling*. United States. doi:10.1093/ptep/ptw083.

```
Seiberg, Nathan, and Witten, Edward. 2016.
"Gapped boundary phases of topological insulators via weak coupling". United States.
doi:10.1093/ptep/ptw083. https://www.osti.gov/servlets/purl/1424001.
```

```
@article{osti_1424001,
```

title = {Gapped boundary phases of topological insulators via weak coupling},

author = {Seiberg, Nathan and Witten, Edward},

abstractNote = {The standard boundary state of a topological insulator in 3 + 1 dimensions has gapless charged fermions. We present model systems that reproduce this standard gapless boundary state in one phase, but also have gapped phases with topological order. Our models are weakly coupled and all the dynamics is explicit. We rederive some known boundary states of topological insulators and construct new ones. Consistency with the standard spin/charge relation of condensed matter physics places a nontrivial constraint on models},

doi = {10.1093/ptep/ptw083},

journal = {Progress of Theoretical and Experimental Physics},

number = 12,

volume = 2016,

place = {United States},

year = {2016},

month = {11}

}

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