Lieb-Robinson bounds via the Combes-Thomas estimate

This paper studies quantum spin systems: networks of spins coupled by local interactions. The Lieb-Robinson bound predicts that in these systems, information propagates at an essentially finite speed. We produce a new proof of this result. Our approach relies on a spectral bound on entries of resolvents of band matrices, the Combes-Thomas estimate, rather than on the standard path-counting argument.