Interdisk spacing effect on resonant properties of Ge disk lattices on Si substrates
A A Shklyaev1,2, D E Utkin3,4, A V Tsarev3,4
1Novosibirsk State University, 2 Pirogov Str., Novosibirsk, 630090, Russia. shklyaev@isp.nsc.ru.
Scientific Reports
|May 17, 2022
Summary
Adjusting germanium disk height and spacing on silicon substrates enhances antireflection properties. Smaller gaps create a short-wavelength reflection minimum, improving light manipulation for advanced applications.
Area of Science:
- Materials Science
- Nanophotonics
- Optics
Background:
- Germanium (Ge) disk lattices on silicon (Si) substrates are investigated for their light reflection characteristics.
- Understanding the influence of geometric parameters on optical properties is crucial for device applications.
Purpose of the Study:
- To investigate the effect of Ge disk height and interdisk gap width on the light reflection properties of Ge disk lattices on Si substrates.
- To explore how varying these parameters influences antireflection capabilities and resonant behaviors.
Main Methods:
- Experimental study of light reflection properties.
- Numerical simulations to analyze resonant fields around Ge disks.
- Systematic variation of disk height and interdisk gap width (down to 500 nm).
Main Results:
- Interdisk spacing effects on reflection were observed even at large gap widths (500 nm).
- Decreasing the gap width introduced a reflection minimum in the short-wavelength region, enhancing antireflection properties.
- This short-wavelength minimum deepened significantly at smaller gap widths, linked to resonant fields between closely spaced disks.
Conclusions:
- Geometrical parameters, specifically short-wavelength minimum-inducing configurations, are critical for optimizing optical properties.
- Tailoring disk height and gap width can significantly enhance antireflection and other resonant properties for applications utilizing collective lattice resonances.
