The electronic contribution to the thermal conductivity can be deduced from the electrical conductivity through the use of the Wiedemann-Franz law . However the thermal conductivity due to phonon heat transfer cannot be measured directly .

自由电子 引起的热导率可以通过电导率，利用 Wiedemann-Franz 定律 得到，声子 引起的热导 率目前 仍然不能进行实验测量，只能借助其他方法来研究。