Specific heat and thermal conductivity in the mixed state of MgB2

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The specific heat C and the electronic and phononic thermal conductivities kappaₑ and kappaph are calculated in the mixed state for magnetic fields H near Hc₂. The effects of supercurrent flow and Andreev scattering of the Abrikosov vortex lattice on the quasiparticles are taken into account. The resulting function C(H) is nearly linear while kappaₑ(H) exhibits an upward curvature near Hc₂. The slopes decrease with impurity scattering which improves the agreement with the data on MgB₂. The ratio of phonon relaxation times tauₙ/tauₛ = g(omega₀,H) for phonon energy omega₀, which is nearly a step function at omega₀ = 2Delta for the BCS state, is smeared out and tends to one for increasing H. This leads to a rapid reduction of kappaph(H) in MgB₂ for relatively small fields due to the rapid suppression of the smaller energy gap.