Complexity as a novel probe of quantum quenches: universal scalings and purifications
Abstract
We apply the recently developed notion of complexity for field theory to a quantum quench through a critical point in 1+1 dimensions. We begin with a toy model consisting of a quantum harmonic oscillator, and show that complexity exhibits universal scalings in both the slow and fast quench regimes. We then generalize our results to a 1-dimensional harmonic chain, and show that preservation of these scaling behaviours in free field theory depends on the choice of norm. Applying our set-up to the case of two oscillators, we quantify the complexity of purification associated to a subregion, and demonstrate that complexity is capable of probing features to which the entanglement entropy is insensitive. We find that the complexity of subregions is subadditive, and comment on potential implications for holography.
Keywords
Cite
@article{arxiv.1807.07075,
title = {Complexity as a novel probe of quantum quenches: universal scalings and purifications},
author = {Hugo A. Camargo and Pawel Caputa and Diptarka Das and Michal P. Heller and Ro Jefferson},
journal= {arXiv preprint arXiv:1807.07075},
year = {2019}
}
Comments
Minor edits and notational improvements; consistent with version published in Phys. Rev. Lett