The effects of different doping patterns on the lattice thermal conductivity of solid Ar

In order to investigate the effects of doping patterns on phonon transport, equilibrium molecular dynamics method is performed to calculate the lattice thermal conductivity of solid argon doped with krypton atoms in different geometrical distribution modes. Four different patterns are introduced through replacing Ar atoms with the same amount of Kr atoms in different volume and positions. The simulation results demonstrate that the impurity volume and distribution have significant effects on phonon transport in a crystal structure. The lowest thermal conductivity among the four doping patterns is achieved by introducing the impurity in a nanometer size cubic pattern distributed in the Ar matrix, which is roughly two times lower than that of pure argon at 17 K. The impurity strength on phonons is estimated through comparing the simulation results with those calculated from the Callaway model.

► Effects of four doping patterns on the thermal conductivity of Ar are studied.
► Lowest value can be achieved by organizing the impurities in a cubic pattern.
► It is attributed to stronger interface scatterings and impurity scatterings.
► Scattering strength is estimated by fitting the results with Callaway model.