Phase transition of a transverse semi-infinite spin-1 Ising model with crystal field

The effect of the surface and bulk transverse fields on the phase diagrams of a semi-infinite spin-1 ferromagnetic Ising model with a crystal field is investigated within a finite cluster approximation with an expansion techn ique for duster identities of spin-1 localized spin systems. Phase diagrams are determined as a function of the ratio of bulk and surface transverse f ields and the ratio of bulk and surface crystal fields. However, the system exhibits a variety of phase transitions and multi-critical points. A dead layer appears in a special region of the space parameters. (C) 1999 Elsevie r Science B.V. All rights reserved.