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arXiv · 1601.01630

Characterizing ground and thermal states of few-body Hamiltonians

Felix Huber·Otfried Gühne
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Abstract

The question whether a given quantum state is a ground or thermal state of a few-body Hamiltonian can be used to characterize the complexity of the state and is important for possible experimental implementations. We provide methods to characterize the states generated by two- and, more generally, k-body Hamiltonians as well as the convex hull of these sets. This leads to new insights into the question which states are uniquely determined by their marginals and to a generalization of the concept of entanglement. Finally, certification methods for quantum simulation can be derived.

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Felix Huber, Otfried Gühne. 2016-06-29. Characterizing ground and thermal states of few-body Hamiltonians. https://doi.org/10.1103/physrevlett.117.010403

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