Thermal insulator transition induced by interface scattering

摘要

We develop an effective medium model of thermal conductivity that accountsfor both percolation and interface scattering. This model accurately explainsthe measured increase and decrease of thermal conductivity with loading incomposites dominated by percolation and interface scattering, respectively. Ourmodel further predicts that strong interface scattering leads to a sharpdecrease in thermal conductivity, or an insulator transition, at high loadingswhen conduction through the matrix is restricted and heat is forced to diffusethrough particles with large interface resistance. The accuracy of our modeland its ability to predict transitions between insulating and conducting statessuggest it can be a useful tool for designing materials with low or highthermal conductivity for a variety of applications.