Quantum Hall states under conditions of vanishing Zeeman energy

Abstract

We report on magneto-transport measurements of a two-dimensional electron gas confined in a Cd${}_{0.997}$Mn${}_{0.003}$Te quantum well structure under conditions of vanishing Zeeman energy. The electron Zeeman energy has been tuned via the $s-d$ exchange interaction in order to probe different quantum Hall states associated with metallic and insulating phases. We have observed that reducing Zeeman energy to zero does not necessary imply the disappearing of quantum Hall states, i.e. a closing of the spin gap. The spin gap value under vanishing Zeeman energy conditions is shown to be dependent on the filling factor. Numerical simulations support a qualitative description of the experimental data presented in terms of a crossing or an avoided-crossing of spin split Landau levels with same orbital quantum number $N$.

References in corpus (7)

• The electronic properties of graphene
• Resistance Spikes at Transitions between Quantum Hall Ferromagnets
• Ising Quantum Hall Ferromagnet in Magnetically Doped Quantum Wells
• Anti-crossings of spin-split Landau levels in an InAs two-dimensional electron gas with spin-orbit coupling
• Landau Level Crossings and Extended-State Mapping in Magnetic Two-dimensional Electron Gases
• Enhancement of the spin-gap in fully occupied two-dimensional Landau levels
• Hysteretic resistance spikes in quantum Hall ferromagnets without domains

Cited by in corpus (3)

• Quantum Hall Effects in Graphene-Based Two-Dimensional Electron Systems
• Fractional Quantum Hall Effect in a Diluted Magnetic Semiconductor
• Mesoscopic transport in electrostatically-defined spin-full channels in quantum Hall ferromagnets