831 citations · 8k across the 103 of their papers we have counts for
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Gapless Hamiltonians for the toric code using the PEPS formalism
Carlos Fernández-González, Norbert Schuch, Michael M. Wolf +2
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 gaple…
Complexity of commuting Hamiltonians on a square lattice of qubits
Norbert Schuch
We consider the computational complexity of Hamiltonians which are sums of commuting terms acting on plaquettes in a square lattice of qubits, and we show that deciding whether the…
Highly Entangled States With Almost No Secrecy
Matthias Christandl, Norbert Schuch, Andreas Winter
In this paper we illuminate the relation between entanglement and secrecy by providing the first example of a quantum state that is highly entangled, but from which, nevertheless,…