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The Landau-Problem on the θ-Deformed Two-Torus

H. Grosse·M. Kornexl
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Abstract

We study the Landau-problem on the $θ$-deformed two-torus and use well-known projective modules to obtain perturbed spectra. For a strong magnetic field B the problem can be restricted to one particular Landau-level. First we represent generators of the algebra of the non-commutative torus as finite dimensional matrices. A second approach leads to a reducible representation with a $θ$-dependent center. For a simple periodic potential, the rational part of the Hofstadter-butterfly spectrum is obtained.

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H. Grosse, M. Kornexl. 2002-10-07. The Landau-Problem on the θ-Deformed Two-Torus. https://arxiv.org/abs/quant-ph/0210042

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