x>ρ_y holds, where ρ_x(y) is the resistivity along the longer (shorter) Fe-Fe axis. In contrast, the opposite anisotropy ρ_x<ρ_y is realized in other undoped Fe-based superconductors. Such nontrivial material dependence is naturally explained in terms of the strongly orbital-dependent inelastic quasiparticle scattering realized in the orbital-ordered state. The opposite anisotropy between FeSe (ρ_x>ρ_y) and other undoped compounds (ρ_x<ρ_y) reflects the difference in the number of hole pockets. We also explain the large in-plane anisotropy of the thermoelectric power in the nematic state.

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