The composition modulation effect during spinodal decomposition of ZnxCd1-xTe solid solutions under conditions of energy resonance

The Cahn-Hillard equation, previously obtained to describe the decomposition of metal solid solutions, is adapted to analyze the spinodal decomposition of A²B⁶ semiconductor solid solutions. The obtained differential equation is used to describe the spinodal decomposition of the Zn_xCd_1-xTe solid solution, which is synthesized under conditions close to the boundaries of absolutely unstable regions on the state diagram of the system. A quantitative description of the composition modulation effect that appears in the material when its growth under the indicated conditions is given.

Computer simulations of the spinodal decomposition of the Zn_xCd_1-xTe solid solution showed that micro oscillations of the material composition are connected by the resonance phenomenon between the excess mixing energy and the energy of elastic strains arising in the inclusions of the new phase coherently conjugated with the lattice of the initial crystal. It is shown that such resonance phenomena are most intense when the conditions for the material synthesis are chosen in the immediate vicinity of the spinodal curves in the phase state diagram of the system.