Publication: Gapless Hamiltonians for the Toric Code Using the Projected Entangled Pair State Formalism
Full text at PDC
Fernández González, Carlos
Wolf, Michael M.
Advisors (or tutors)
American Physical Society
We study Hamiltonians which have Kitaev's toric code as a ground state, and show how to construct a Hamiltonian which shares the ground space of the toric code, but which has gapless excitations with a continuous spectrum in the thermodynamic limit. Our construction is based on the framework of projected entangled pair states, and can be applied to a large class of two-dimensional systems to obtain gapless "uncle Hamiltonians."
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