Spin-dependent magneto-transport in bilayer WSe₂

We report magneto-transport measurements in bilayer WSe₂, showing electrons behave distinctly in Landau level (LL) of different spins. The conductivity at half-filled minority-spin Landau levels is much lower than in majority-spin and diminishes at high field with electrons completely localized. Also, the temperature-dependent conductance behaves opposite in different spin LLs, with an unusual trend of conductance decreasing with lowering temperature at half-filled minority-spin Landau levels. We further observe a similar phenomenon happening in the valley pseudo-spin when changing the degree of polarization with displacement field. The higher pseudo-spin polarization of valence charges results in higher magneto-resistance. These phenomena can be understood with a polaron-like picture. Finally, magneto-transport demonstrates a sharp majority-minority spin-state transition close to the LL crossing density at partial filling LL. The spike of two-probe conductance signals first-order transition and domain walls of two different spin states.