Equilibrium molecular dynamics method is performed to calculate the lattice thermal conductivities of solid argon doped with krypton in different geometrical distributions. The effects of centralization doping, monolayer doping, uniform doping, non-uniform doping, random doping and cubic pattern doping on the thermal conductivity of argon crystal are investigated respectively. The results demonstrate that, the uniformity of the impurity distribution plays a critical role in the thermal conductivity of solid argon. It is found that the lowest thermal conductivity could be achieved by organizing the impurity in a cubic pattern. Because both the phonon-impurity scattering and the stronger phonon-interface scattering can destroy the coherence of phonons. Calculation results suggest that the minimum thermal conductivity value among six different kinds of impurity arrangements is roughly 1.90 times lower than that of pure argon under the temperature of 17K. However, the values of thermal conductivity are almost the same as those of pure argon at higher temperatures.
Thermal expansion and impurity effects on lattice thermal conductivity of solid argon
