The critical exponents of the β-(2 x 4) → α(2 x 4) reconstruction phase transition on the (001) GaAs surface were determined experimentally. It was found that the phase transition was analogous to a van der Waals transition. The critical parameters were measured experimentally. The mean field theory was applied, and three-parameter isotherms were obtained that agree with the experimental results at the following values of the parameters: Est = 0.36eV, ΔE = 0.18eV, and Ei = 0.134eV. Precision measurements of the critical exponents β and δ were carried out. Their values, β = 1/8 and δ = 15, indicated that the phase transition was truly 2-dimensional.

Critical Phenomena in the β-(2 x 4) → α(2 x 4) Reconstruction Transition on the (001) GaAs Surface. Y.G.Galitsyn, D.V.Dmitriev, V.G.Mansurov, S.P.Moshchenko, A.I.Toropov: JETP Letters, 2005, 81[12], 629-33