Entanglement entropy in excited states of the quantum Lifshitz model. (30th May 2017)

• Record Type: Journal Article
• Authors: Parker, Daniel E; Vasseur, Romain; Moore, Joel E
• Is Part Of: Journal of physics. Volume 50:Number 25(2017)
• Publication Date: 2017-05-30
• Subjects: entanglement entropy -- quantum Lifshitz model -- excited state entanglement; Mathematical physics -- Periodicals; Statistical physics -- Periodicals; Quantum theory -- Periodicals; Matter -- Properties -- Periodicals; 530.105
• DOI: 10.1088/1751-8121/aa70b3
• Languages: English
• ISSNs: 1751-8113

Abstract

Abstract: We investigate the entanglement properties of an infinite class of excited states in the quantum Lifshitz model (QLM). The presence of a conformal quantum critical point in the QLM makes it unusually tractable for a model above one spatial dimension, enabling the ground state entanglement entropy for an arbitrary domain to be expressed in terms of geometrical and topological quantities. Here we extend this result to excited states and find that the entanglement can be naturally written in terms of quantities which we dub 'entanglement propagator amplitudes' (EPAs). EPAs are geometrical probabilities that we explicitly calculate and interpret. A comparison of lattice and continuum results demonstrates that EPAs are universal. This work shows that the QLM is an example of a 2 + 1d field theory where the universal behavior of excited-state entanglement may be computed analytically.