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Cantor Spectra for Double Exchange Model

Atsuo Satou·Masanori Yamanaka
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Abstract

We numerically study energy spectra and localization properties of the double exchange model at irrational filling factor. To obtain variational ground state, we use a mumerical technique in momentum space by ``embedded'' boundary condition which has no finite size effect a priori. Although the Hamiltonian has translation invariance, the ground state spontaneously exhibits a self-similarity. Scaling and multi-fractal analysis for the wave functions are performed and the scaling indices $α$'s are obtained. The energy spectrum is found to be a singular continuous, so-called the Cantor set with zero Lebesque measure.

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Atsuo Satou, Masanori Yamanaka. 2001-03-26. Cantor Spectra for Double Exchange Model. https://doi.org/10.1103/physrevb.63.212403

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