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Effective Bragg conditions in a one-dimensional quasicrystal
W J Hsueh1, C H Chang, Y H Cheng
1Department of Engineering Science, National Taiwan University, Taipei, Taiwan. hsuehwj@ntu.edu.tw
Optics Express
|November 29, 2012
Summary
This study reveals that Fibonacci superlattices, a type of quasicrystal, exhibit two effective Bragg conditions. This leads to omnidirectional, wideband, and high reflectance properties in these quasiperiodic materials.
Area of Science:
- Condensed matter physics
- Materials science
- Optics
Background:
- Periodic structures exhibit Bragg conditions, leading to high reflectance.
- Quasicrystals possess unique structural properties not found in periodic materials.
Purpose of the Study:
- To investigate the occurrence of effective Bragg conditions in Fibonacci superlattices.
- To explore the reflectance properties of these one-dimensional quasicrystals.
- To compare the optical behavior of quasicrystals with traditional periodic structures.
Main Methods:
- Analysis of effective Bragg conditions in Fibonacci superlattices.
- Theoretical modeling of reflectance in quasiperiodic materials.
Main Results:
- Observed two effective Bragg conditions in Fibonacci superlattices, unlike the single condition in periodic structures.
- Demonstrated wide gapwidth and high reflectance associated with these conditions.
- Proposed the existence of omnidirectional and wideband high reflectance.
Conclusions:
- Fibonacci superlattices exhibit unique optical properties due to their quasiperiodic nature.
- The findings suggest potential applications in optical devices requiring broadband and omnidirectional reflection.
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