%0 Journal Article
%J Physical Review Letters
%D 2015
%T Nearly-linear light cones in long-range interacting quantum systems
%A Michael Foss-Feig
%A Zhe-Xuan Gong
%A Charles W. Clark
%A Alexey V. Gorshkov
%X In non-relativistic quantum theories with short-range Hamiltonians, a velocity $v$ can be chosen such that the influence of any local perturbation is approximately confined to within a distance $r$ until a time $t \sim r/v$, thereby defining a linear light cone and giving rise to an emergent notion of locality. In systems with power-law ($1/r^{\alpha}$) interactions, when $\alpha$ exceeds the dimension $D$, an analogous bound confines influences to within a distance $r$ only until a time $t\sim(\alpha/v)\log r$, suggesting that the velocity, as calculated from the slope of the light cone, may grow exponentially in time. We rule out this possibility; light cones of power-law interacting systems are algebraic for $\alpha>2D$, becoming linear as $\alpha\rightarrow\infty$. Our results impose strong new constraints on the growth of correlations and the production of entangled states in a variety of rapidly emerging, long-range interacting atomic, molecular, and optical systems.
%B Physical Review Letters
%V 114
%P 157201
%8 2015/04/13
%G eng
%U http://arxiv.org/abs/1410.3466v1
%N 15
%! Phys. Rev. Lett.
%R 10.1103/PhysRevLett.114.157201