The effect of metal-nonmetal transition on the low-temperature magnetothermal conductivity of boron doped silicon

An improvement in the theoretical treatment of the reduced magneto-thermal conductivity of a boron-doped silicon sample having shallow acceptors with p=9.0x1016cm-3 is presented. It is shown that this impurity concentration lies in the intermediate region and use is made of Mikoshiba's inhomogeneity model to include in the calculation both the relaxation rates for bound hole-phonon and free hole-phonon scatterings. The results cover a range of temperature from 1-5 deg. K and magnetic fields up to 55 KG. Good agreement is found up to about 25 KG. For higher fields the agreement is poor emphasising the necessity of including more details of the scattering mechanism in the calculations. The overall agreement is improved when compared to previous works. (author)