Frequency dependent conductivity in the integer quantum Hall effect

A. Bäker; L. Schweitzer

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arXiv · cond-mat/9908123

Frequency dependent conductivity in the integer quantum Hall effect

A. Bäker·L. Schweitzer

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Abstract

Frequency dependent electronic transport is investigated for a two-dimensional disordered system in the presence of a strong perpendicular static magnetic field. The ac-conductivity is calculated numerically from Kubo's linear response theory using a recursive Green's function technique. In the tail of the lowest Landau band, we find a linear frequency dependence for the imaginary part of $σ_{xx}(ω)$ which agrees well with earlier analytical calculations. On the other hand, the frequency dependence of the real part can not be expressed by a simple power law. The broadening of the $σ_{xx}$-peak with frequency in the lowest Landau band is found to exhibit a scaling relation from which the critical exponent can be extracted.

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BibTeX RIS

A. Bäker, L. Schweitzer. 1999-08-09. Frequency dependent conductivity in the integer quantum Hall effect. https://arxiv.org/abs/cond-mat/9908123

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