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Hofstadter butterfly as Quantum phase diagram

D. Osadchy·J. Avron
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Abstract

The Hofstadter butterfly is viewed as a quantum phase diagram with infinitely many phases, labelled by their (integer) Hall conductance, and a fractal structure. We describe various properties of this phase diagram: We establish Gibbs phase rules; count the number of components of each phase, and characterize the set of multiple phase coexistence.

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D. Osadchy, J. Avron. 2001-02-20. Hofstadter butterfly as Quantum phase diagram. https://doi.org/10.1063/1.1412464

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