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Updated: Jun 30, 2026
08:04
Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Excitonic polaritons in Fibonacci quasicrystals
J Hendrickson1, B C Richards, J Sweet
1College of Optical Sciences, The University of Arizona, Tucson, AZ 85721, USA. jhendrickson@optics.arizona.edu
Optics Express
|October 1, 2008
Summary
Researchers developed novel light-emitting photonic quasicrystals using GaAs/AlGaAs quantum wells. These quasicrystals exhibit strong light emission due to excitonic resonances, offering advantages over traditional photonic crystals.
Area of Science:
- Condensed matter physics
- Materials science
- Optoelectronics
Background:
- One-dimensional photonic quasicrystals offer unique optical properties due to their quasi-periodic structures.
- Excitonic resonances in quantum wells are crucial for light-matter interactions and emission.
Purpose of the Study:
- To fabricate and characterize light-emitting one-dimensional photonic quasicrystals.
- To investigate the role of excitonic resonances in the optical properties of these quasicrystals.
- To compare the light-emitting capabilities of photonic quasicrystals with photonic crystals.
Main Methods:
- Molecular-beam epitaxy (MBE) for growing high-quality GaAs/AlGaAs quantum wells.
- Fabrication of one-dimensional photonic quasicrystals with Fibonacci sequences.
- Optical characterization using reflectivity and photoluminescence spectroscopy.
Main Results:
- Successful fabrication of photonic quasicrystals with wavelength-scale spacings following a Fibonacci sequence.
- Observation of polaritonic effects arising from resonant light-matter coupling (excitonic polaritons).
- Photoluminescence experiments demonstrated strong light emission from the quasicrystal structures, attributed to the interplay of long-range order and lack of periodicity.
Conclusions:
- Active photonic quasicrystals can function as efficient light emitters.
- The unique structure of quasicrystals, combining long-range order with non-periodicity, enhances light emission compared to periodic photonic crystals.
- Excitonic polariton theory accurately describes the observed optical phenomena in these novel structures.
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