A note on magnetic-field induced level-density condensation in a two-dimensional electron gas with point scatterers

N. Kumar; Nivedita Deo

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A note on magnetic-field induced level-density condensation in a two-dimensional electron gas with point scatterers

N. Kumar·Nivedita Deo

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Abstract

The density-of-states (DOS) for a magnetized (B) two-dimensional electron gas (2DEG) containing point scatterers of arbitrary strengths, concentration ($n_s$) and distribution is analyzed. It is shown from the first principles that for $n_s \leq B/Φ_o \equiv n_B$, the areal density of flux quanta $Φ_o \equiv hc/e$, the DOS retains the extensive degeneracy characteristic of the Landau levels, but reduced by a factor $(1 - {n_s}/{n_B})$. This elementary but exact result gives a level condensation for magnetic field $B > n_sΦ_o$, as first noted by Brézin {\em et al.}. Its implications for the Integral Quantum Hall Effect and for Random Matrix Theory are pointed out.

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N. Kumar, Nivedita Deo. 1996-08-02. A note on magnetic-field induced level-density condensation in a two-dimensional electron gas with point scatterers. https://arxiv.org/abs/cond-mat/9608005

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