Failure of renormalisation group method in semiclassical limit

Publisher Website
Google Scholar
Abstract
The authors compute the ground state energy of a Heisenberg linear chain antiferromagnet for spins s=1/2, 1 . . . infinity by a block renormalisation method. Although this method yields reasonably accurate results in the quantum limit s=1/2, in the semiclassical limit (where the significant parameter in the asymptotic expansion e0=-Js2(1+ gamma /2s+O(1/s)2) is known to be gamma approximately=0.7) the RG procedure yields gamma =0, a highly unsatisfactory result.