Level spacing statistics of disordered finite superlattices spectra and motional narrowing as a random matrix theory effect

R. R. Rey-Gonzalez; P. A. Schulz

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arXiv · cond-mat/9909341

Level spacing statistics of disordered finite superlattices spectra and motional narrowing as a random matrix theory effect

R. R. Rey-Gonzalez·P. A. Schulz

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Abstract

In the present work the problem of coupled disordered quantum wells is addressed in a random matrix theory framework. The quantum wells are short repulsive binary alloys embeded by ordered barriers and show well defined quantized levels as a consequence of spatial confinement. Finite disordered superlattices may show both diffusive-like and localized minibands. Three different level repulsion suppression mechanisms are discussed by analysing the evolution of nearest-level-spacing distribution function within each superlattice miniband. The present numerical results show a motional narrowing effect, which is in fact a consequence of the random matrix theory.

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R. R. Rey-Gonzalez, P. A. Schulz. 1999-09-23. Level spacing statistics of disordered finite superlattices spectra and motional narrowing as a random matrix theory effect. https://arxiv.org/abs/cond-mat/9909341

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