Two-dimensional Zn Research Articles

Continuum limit of the two-dimensional ZN spin model

A Continuum limit of the two-dimensional Z N spin model is found and classical field equations are derived. It is also shown that in its first approximation this field theory reduces toe Villain form of the spin system.

Adsorption of Zn on GaAs

The interaction of a Zn atomic beam with clean, well-ordered GaAs surfaces of (100), (111) and ( 1 1 1 ) orientation was studied by LEED, RED, Auger spectroscopy and mass spectrometric measurements of the desorbing Zn flux. Adsorption occurs by formation of two-dimensional Zn islands with the adsorption rate dependent on collisions between mobile, physically adsorbed Zn atoms with the island boundaries. The islands are ordered with respect to the substrate with the (0001) plane parallel to the surface. Desorption occurs with an activation energy equal to the enthalpy of vaporization of pure Zn; however, a small amount( ∼ 1 × 10 13 atoms cm 2 ) of Zn is more strongly bound to the substrate and appears to form the nucleation centers for island growth. An increased As content of the surface increases the concentration of strongly bound Zn which is probably Zn in Ga surface vacancies.