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Flat-band excitonic states in Kagome lattice on semiconductor surface

H. Ishii·T. Nakayama·J. Inoue
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Abstract

Excitonic properties in the Kagome lattice system, which is produced by quantum wires on semiconductor surfaces, are investigated by using the exact diagonalization of a tight binding model. It is shown that due to the existence of flat bands the binding energy of exciton becomes remarkably large in the two-dimensional Kagome lattice compared to that in one-dimensional lattice, and the exciton Bohr radius is quite small as large as a lattice constant. We also discuss the magnetic field effects on the exciton binding energy and the stability of exciton against the creation of charged exciton and biexciton.

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H. Ishii, T. Nakayama, J. Inoue. 2001-10-18. Flat-band excitonic states in Kagome lattice on semiconductor surface. https://doi.org/10.1016/s0039-6028(02)01630-8

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