The scaling behavior of the entanglement entropy in 2+1 dimensional critical systems

Abstract

The entanglement entropy in 1+1 dimensional critical system has been well studied and known to have a universal scaling form that gives information about the underlying critical system. While the case for 1+1 dimensional critical systems has been well studied, the situation in higher dimensional systems is less clear. In this work, I show that the entanglement entropy in a certain class of 2+1 dimensional critical systems, the conformal quantum critical theories, has a universal subleading correction that likewise gives information about the underlying critical system. In addition, I address the issue of whether the dynamical entanglement entropy, the entanglement generated by a local quantum quench, is an experimentally measurable quantity. This turns out not to be the case, but to arrive at this conclusion we studied quenching in a theory of strongly interacting electrons and applied methods of boundary conformal field theory to solve a hitherto open problem: the noise from an instantaneous switching of a quantum point contact separating two fractional quantum Hall fluids.