Misfit tension in heterostructures on the base of A4B6 materials

The results of the heterostructure (Pb0.8Sn0.2Te/PbSe0.08Te0.02 and Pb0.8Sn0.2Te/PbS0.05Te0.95) composition analysis for thickness are used to estimate the values of lattice parameter misfit in the transition layer. Change in the Young modulus values and the Poison coefficient according to the transition layer thickness is determined from the experiments investigating the velocities of longitudinal and cross-section ultrasound along the (100) crystallographic direction for solid solutions Pb0.8Sn0.2Te, PbSe0.08Te0.92 and PbS0.05Te095. The F(Δa) misfit tension values in the heterostructures grown up on the PbS0.05Te0.95 substrates is shown to exceed the F(Δa) value for heterostructures prepared on the PbSe0.08-Te0.92 substrates 5 times. It should be also marked that temperature decrease up to 40-50 K can cause considerable increase of misfit tensions in heterostructures Pb0.8Sn9.2Te/PbS0.05Te0.95 due to the presence of the phase transition in the PbS0.05Te0.95 solid solution in this temperature range, that can influence the ellastic module values