Quantum Hall Effect in Spin-Degenerate Landau Levels: Spin-Orbit Enhancement of the Conductivity

D. G. Polyakov, M. E. Raikh
1995 Physical Review Letters  
The quantum Hall regime in a smooth random potential is considered when two disorder-broadened Zeeman levels overlap strongly. Spin-orbit coupling is found to cause a drastic change in the percolation network which leads to a strong enhancement of the dissipative conductivity at finite temperature, provided the Fermi level E_F lies between the energies of two delocalized states E=±Δ, 2Δ being the Zeeman splitting. The conductivity is shown to exhibit a box-like behavior with changing magnetic
more » ... eld: σ_xx is ∼ e^2/h at |E_F|<Δ and exponentially small otherwise. Two peaks of σ_xx arising as T→ 0 are found to be strongly asymmetric.
doi:10.1103/physrevlett.75.1368 pmid:10060275 fatcat:xflortgwyzc2lmm6jeeqlby4yi