Short--range impurity in the vicinity of a saddle point and the levitation of the 2D delocalized states in a magnetic field

Abstract

The effect of a short--range impurity on the transmission through a saddle--point potential for an electron, moving in a strong magnetic field, is studied. It is demonstrated that for a random position of an impurity and random sign of its potential the impurity--induced mixing of the Landau levels diminishes {\em on average} the transmission coefficient. This results in an upward shift (levitation) of the energy position of the delocalized state in a smooth potential. The magnitude of the shift is estimated. It increases with decreasing magnetic field $B$ as $B^{-4}$.

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References in corpus (5)

• Global phase diagram for the quantum Hall effect: An experimental picture
• Floating of Extended States and Localization Transition in a Weak Magnetic Field
• Weak Field Phase Diagram for an Integer Quantum Hall Liquid
• Weak levitation of 2D delocalized states in a magnetic field.
• DESTRUCTION OF THE QUANTUM HALL EFFECT WITH INCREASING DISORDER

Cited by in corpus (10)

• Metal-insulator transitions and the effects of electron-electron interactions in two-dimensional electron systems
• Landau Level Mixing and Levitation of Extended States in Two Dimensions
• Quantum Hall - insulator transitions in lattice models with strong disorder
• Levitation of Current Carrying States in the Lattice Model for the Integer Quantum Hall Effect
• Levitation of quantum Hall critical states in a lattice model with spatially correlated disorder
• Quantifying the levitation picture of extended states in lattice models
• Topological Phase Diagram of a Two-Subband Electron System
• Quasiclassical approach to the weak levitation of extended states in the quantum Hall effect
• Weakly chiral networks and 2D delocalized states in a weak magnetic field
• Phase diagram of weak-magnetic-field quantum Hall transition quantified from classical percolation