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arXiv · 1111.5817

Gapless Hamiltonians for the toric code using the PEPS formalism

Carlos Fernández-González·Norbert Schuch·Michael M. Wolf·J. Ignacio Cirac·David Pérez-García
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Abstract

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 (PEPS), and can be applied to a large class of two-dimensional systems to obtain gapless "uncle Hamiltonians".

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Carlos Fernández-González, Norbert Schuch, Michael M. Wolf, J. Ignacio Cirac, David Pérez-García. 2011-11-28. Gapless Hamiltonians for the toric code using the PEPS formalism. https://doi.org/10.1103/physrevlett.109.260401

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