Monday, July 18th, 2011 - 3.00 p.m.
Building E - Room 1

Giuseppe Vitagliano - University of Bilbao

Abstract:
We address the question whether a Hamiltonian with only nearest
neighbor interaction can have a highly entangled ground state, in the
sense that it presents a volume law scaling of the block entanglement
entropy. For typical quantum systems the block entanglement entropy
of the ground state follows an area-law scaling, with a logarithmic
violation for quantum critical models. Nevertheless, we explicitly
construct a spin-1/2 chain Hamiltonian that has the expected properties,
breaking the translational invariance of the model. Its ground state
is characterized by an accumulation of singlet bonds across the half
chain.This result is also related to the QMA completeness of the 1D
local Hamiltonian problem.