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Optical absorption in Fibonacci lattices at finite temperature

A. Rodriguez·F. Dominguez-Adame
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Abstract

We consider the dynamics of Frenkel excitons on quasiperiodic lattices, focusing our attention on the Fibonacci case as a typical example. We evaluate the absorption spectrum by solving numerically the equation of motion of the Frenkel-exciton problem on the lattice. Besides the main absorption line, satellite lines appear in the high-energy side of the spectra, which we have related to the underlying quasiperiodic order. The influence of lattice vibrations on the absorption line-shape is also considered. We find that the characteristic features of the absorption spectra should be observable even at room temperature. Consequently, we propose that excitons act as a probe of the topology of the lattice even when thermal vibrations reduce their quantum coherence.

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BibTeXRIS

A. Rodriguez, F. Dominguez-Adame. 1997-07-24. Optical absorption in Fibonacci lattices at finite temperature. https://doi.org/10.1103/physrevb.56.10737

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