Journal of Physics A Mathematical and General

Inhomogeneous Ising chain in a transverse field: finite-size scaling and asymptotic conformal spectrum

Bertrand Berche, Loïc Turban

Published Jul 7, 1990• 21 citations

Abstract

The quantum version of the Hilhorst-van Leeuwen model i.e. an inhomogeneous Ising model in a transverse field with a marginal perturbation of the bulk interaction varying like l -1 with the distance l from the surface is studied numerically on a finite chain with symmetric interactions using fermion techniques and finite-size scaling at the bulk critical point. The surface exponents for the energy and the magnetisation are respectively x e =2 alpha +2, x m = alpha +1/2 when alpha >or= alpha c and x e =- alpha +1/2, x m =0 and x' m =- alpha -1/2 when alpha <or= alpha c where alpha c =-1/2 is the critical value of the perturbation amplitude below which the surface becomes ordered at the bulk critical point.

DOI: 10.1088/0305-4470/23/13/037

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