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Surface Incommensurate Structure in an Anisotropic Model with competing interactions on Semiinfinite Triangular Lattice

P. Pajersky·A. Surda
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Abstract

An anisotropic spin model on a triangular semiinfinite lattice with ferromagnetic nearest-neighbour interactions and one antiferromagnetic next-nearest-neighbour interaction is investigated by the cluster transfer-matrix method. A phase diagram with <2> antiphase, ferromagnetic, incommensurate, and disordered phase is obtained. The bulk uniaxial incommensurate structure modulated in the direction of the competing interactions is found between the <2> antiphase and the disordered phase. The incommensurate structure near the surface with free and <2> boundary condition is studied at different temperatures. Paramagnetic damping at the surface and enhancement of the incommensurate structure in the subsurface region at high temperatures and a new subsurface incommensurate structure modulated in two directions at low temperatures are found.

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P. Pajersky, A. Surda. 1996-11-25. Surface Incommensurate Structure in an Anisotropic Model with competing interactions on Semiinfinite Triangular Lattice. https://doi.org/10.1088/0305-4470%2F30%2F12%2F010

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