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arXiv · 2402.10514

Flat-band engineering of quasi-one-dimensional systems via supersymmetric transformations

Vit Jakubsky·Kevin Zelaya
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Abstract

We introduce a systematic method to spectrally design quasi-one-dimensional crystal models described by the Dirac equation in the low-energy regime. The method is based on the supersymmetric transformation applied to an initially known pseudo-spin-1/2 model. This allows extending the corresponding susy partner so that the new model describes a pseudo-spin-1 system. The spectral design allows the introduction of a flat-band and discrete energies at will into the new model. The results are illustrated in two examples where the Su-Schriefer-Heeger chain is locally converted into a stub lattice.

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Vit Jakubsky, Kevin Zelaya. 2024-02-16. Flat-band engineering of quasi-one-dimensional systems via supersymmetric transformations. https://doi.org/10.1103/physrevb.109.245406

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