Deconfined quantum critical point on the triangular lattice
In this work we propose a theory for the deconfined quantum critical point (DQCP) for spin-1/2 systems on a triangular lattice, which is a direct unfine-tuned quantum phase transition between the standard “√3×√3” noncollinear antiferromagnetic order (or the so-called 120^{∘} state) and the “√12×√12”...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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American Physical Society
2018
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| Online Access: | http://hdl.handle.net/1721.1/115319 |
| _version_ | 1826195555207872512 |
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| author | Jian, Chao-Ming Thomson, Alex Rasmussen, Alex Bi, Zhen Xu, Cenke |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Jian, Chao-Ming Thomson, Alex Rasmussen, Alex Bi, Zhen Xu, Cenke |
| author_sort | Jian, Chao-Ming |
| collection | MIT |
| description | In this work we propose a theory for the deconfined quantum critical point (DQCP) for spin-1/2 systems on a triangular lattice, which is a direct unfine-tuned quantum phase transition between the standard “√3×√3” noncollinear antiferromagnetic order (or the so-called 120^{∘} state) and the “√12×√12” valence solid bond (VBS) order, both of which are very standard ordered phases often observed in numerical simulations. This transition is beyond the standard Landau-Ginzburg paradigm and is also fundamentally different from the original DQCP theory on the square lattice due to the very different structures of both the magnetic and VBS order on frustrated lattices. We first propose a topological term in the effective-field theory that captures the “intertwinement” between the √3×√3 antiferromagnetic order and the √12×√12 VBS order. Then using a controlled renormalization-group calculation, we demonstrate that an unfine-tuned direct continuous DQCP exists between the two ordered phases mentioned above. This DQCP is described by the N[subscript f]=4 quantum electrodynamics (QED) with an emergent PSU(4)=SU(4)/Z₄ symmetry only at the critical point. The aforementioned topological term is also naturally derived from the N[subscript f] = 4 QED. We also point out that physics around this DQCP is analogous to the boundary of a 3d bosonic symmetry- protected topological state with only on-site symmetries. |
| first_indexed | 2024-09-23T10:14:34Z |
| format | Article |
| id | mit-1721.1/115319 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T10:14:34Z |
| publishDate | 2018 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/1153192022-09-30T19:53:34Z Deconfined quantum critical point on the triangular lattice Jian, Chao-Ming Thomson, Alex Rasmussen, Alex Bi, Zhen Xu, Cenke Massachusetts Institute of Technology. Department of Physics Bi, Zhen In this work we propose a theory for the deconfined quantum critical point (DQCP) for spin-1/2 systems on a triangular lattice, which is a direct unfine-tuned quantum phase transition between the standard “√3×√3” noncollinear antiferromagnetic order (or the so-called 120^{∘} state) and the “√12×√12” valence solid bond (VBS) order, both of which are very standard ordered phases often observed in numerical simulations. This transition is beyond the standard Landau-Ginzburg paradigm and is also fundamentally different from the original DQCP theory on the square lattice due to the very different structures of both the magnetic and VBS order on frustrated lattices. We first propose a topological term in the effective-field theory that captures the “intertwinement” between the √3×√3 antiferromagnetic order and the √12×√12 VBS order. Then using a controlled renormalization-group calculation, we demonstrate that an unfine-tuned direct continuous DQCP exists between the two ordered phases mentioned above. This DQCP is described by the N[subscript f]=4 quantum electrodynamics (QED) with an emergent PSU(4)=SU(4)/Z₄ symmetry only at the critical point. The aforementioned topological term is also naturally derived from the N[subscript f] = 4 QED. We also point out that physics around this DQCP is analogous to the boundary of a 3d bosonic symmetry- protected topological state with only on-site symmetries. 2018-05-11T15:13:20Z 2018-05-11T15:13:20Z 2018-05 2018-04 2018-05-10T18:00:24Z Article http://purl.org/eprint/type/JournalArticle 2469-9950 2469-9969 http://hdl.handle.net/1721.1/115319 Jian, Chao-Ming et al. "Deconfined quantum critical point on the triangular lattice." Physical Review B 97, 19 (May 2018): 195115 © 2018 American Physical Society en http://dx.doi.org/10.1103/PhysRevB.97.195115 Physical Review B Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. American Physical Society application/pdf American Physical Society American Physical Society |
| spellingShingle | Jian, Chao-Ming Thomson, Alex Rasmussen, Alex Bi, Zhen Xu, Cenke Deconfined quantum critical point on the triangular lattice |
| title | Deconfined quantum critical point on the triangular lattice |
| title_full | Deconfined quantum critical point on the triangular lattice |
| title_fullStr | Deconfined quantum critical point on the triangular lattice |
| title_full_unstemmed | Deconfined quantum critical point on the triangular lattice |
| title_short | Deconfined quantum critical point on the triangular lattice |
| title_sort | deconfined quantum critical point on the triangular lattice |
| url | http://hdl.handle.net/1721.1/115319 |
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