Anomalous thermal conductivity enhancement in the mixed state of MgB2
MgB2混合态热导率的反常增强

The thermal conductivity of MgB2 polycrystalline sample in the mixed state has been investigated as a function of magnetic field (0-7 T) and temperature (5-45 K). The thermal conductivity increased rapidly in low magnetic fields, and became saturation in higher fields. This behaviour correlates with the two-gap electronic structure of MgB2. Analysis indicates that the remarkable en hancement of thermal conductivity of MgB2 polycrystalline sample in the mixed state cannot be completely attributed to the electronic contribution.