The damage spreading of the Ising model on various two-dimensional trivalent structures with Glauber dynamics is investigated. It is shown that topology plays an important role in determining the damage spreading transition temperatures of the trivalent structures. When damage is considered in terms of only the topological properties of the cellular patterns, the transition temperature above which damage is saturated is found to be determined by the cells with the highest edge number. When the area of cells is also taken into account in the computation of damage, the damage spreading transition temperatures are all lowered. These results are verified by simulation on a set of hierarchical lattices constructed by recursive application of the star-triangle transformation on the vertices of the hexagonal structure, as well as soap froth and randomized lattice structures using Voronoi construction.

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The damage spreading of the Ising model on several two-dimensional trivalent structures, including soap froth, Voronoi, and hierarchical structures, are studied with competing Glauber and Kawasaki dynamics. The damage spreading transition temperature T d and the Curie temperature T C of these structures are compared. We find that T d of the hierarchical lattices decreases sharply as the probability of occurrence of Kawasaki dynamics increases, whereas for soap froth and Voronoi, T d for the Voronoi and soap froth remain nearly unchanged except when the dynamics is dominated by Kawasaki dynamics. T d and T C in our two-dimensional structures are nearly the same and they behave similarly as we change the relative probability of occurrence of the Glauber and Kawasaki dynamics. A heuristic argument is provided to explain the numerical results.

The possibility of pressure-induced increase of exciton-LO-phonon coupling in ZnCdSe/ZnSe quantum wells is studied. The ground state binding energies of the heavy hole excitons are calculated using a variational method with consideration of the electron-phonon interaction and the pressure dependence of the parameters. The results show that for quantum wells with intermediate well width, the exciton binding energy and the LO-phonon energy may coincide in the course of pressure increasing, resulting in the increase of exciton-LO-phonon coupling. It is also found that among the pressure-dependent parameters, the influence of the lattice constant is the most important one. The changes of both the effective masses and the dielectric constants have obvious effects on the exciton binding energy, but their influences are counterbalanced.