Adiabatic paths of Hamiltonians, symmetries of topological order, and automorphism codes
Mar 21, 2022
36 pages
Published in:
- Phys.Rev.B 106 (2022) 8, 085122
- Published: Aug 15, 2022
e-Print:
- 2203.11137 [quant-ph]
DOI:
- 10.1103/PhysRevB.106.085122 (publication)
View in:
Citations per year
Abstract: (APS)
The recent “honeycomb code” is a fault-tolerant quantum memory defined by a sequence of checks, which implements a nontrivial automorphism of the toric code. We argue that a general framework to understand this code is to consider continuous adiabatic paths of gapped Hamiltonians and we give a conjectured description of the fundamental group and second and third homotopy groups of this space in two spatial dimensions. A single cycle of such a path can implement some automorphism of the topological order of that Hamiltonian. We construct such paths for arbitrary automorphisms of two-dimensional doubled topological order. Then, realizing this in the case of the toric code, we turn this path back into a sequence of checks, constructing an automorphism code closely related to the honeycomb code.Note:
- 36 pages, 10 figures; v2: additional references and minor revisions
- phase: topological
- symmetry: topological
- dimension: 2
- Hamiltonian
- adiabatic
- homotopy
References(33)
Figures(10)
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